Monday 7 October 2013

CURRICULUM VITAE OF -Dr. Amar Nath Giri ( 1978)


CURRICULUM VITAE
Present employer  ; NAGARJUNA GROUP

OCTOBER 2007- TILL NOW 
ENVIRONMENT, HEALTH, SAFETY & QUALITY DIVISION
Dr. Amar Nath Giri (1978) –Ex IGIDR , MUMBAI &  IIM- Lucknow Research Associate.
Qualifications: B.Sc (Z.B.C.); M.Sc. Environmental Science; P.G.D. in Environmental Protection Law, Certificate In Environmental studies, Ph.D.  Environmental Science (2005), Lucknow University, Worked as a Research Associate (1-Environmental Management & law 2. Agriculture management Center) at IIM Lucknow.
Group: Environmental science, Management & law, 
Working Area(s): Environmental science, Env. Biology, Env. Education, Env.Awareness; Environmental Laws & Management; Publishing Magazine, Newsletter, Booklets, Organizing Env. Programmes.
Research Area(s): Environmental Policy, Laws, Regulation and Management; Sustainable Development & Environmental laws; Solid Waste Management; Disaster Management; Industrial Pollution Control, Impact of pollution on Plants & animals, Pollution Monitoring. Bio-energy / Remote Sensing Application.
  • Organised INDO-RUSSIAN Joint Seminar on “Institutional Reforms and Development Units in Transitional Economy” in collaboration with Russian Academy of Sciences, ICSSR under Indo-Russian Joint Commission for Cooperation in Social Sciences, IGIDR, Mumbai, February 12 & 13, 2007.
  • Was a Delegate in International Industrial Relation Association  (IIRA) Asian Regional Congress on topic “ The Changing Global Labour Market – Challenges and Opportunities for Asia” At Hotel Ashok, New Delhi, India 19-21 April, 2007.
 
Ph.D Awarded  in 2005
Faculty of Science – Department of Botany
Environmental Science
“Environmental Impact of Industries on Agricultural Crops and Critical Studies of Existing Regulatory Governance for Highly Polluting Industries in India”
DOCTORAL THESIS
By
Amar Nath Giri
I.I.M. Fellow
M.Sc. (Envl.Sc.), P.G.D.E.P.L.
Co-Supervisor                                                              Supervisor
Dr. S.P. Trivedi                                                              Dr. Y.K. Sharma
2005 (INDIA)
COVERED CONTENTS
List of Abbreviations (I and II)
9
I Part
10-136
Preface
11-13
CHAPTER I    - Introduction 
14-33
CHAPTER II - Review literature
34-68
CHAPTER III - Materials and methods
69-78
CHAPTER IV- Results and discussions
·         Pulp and paper mill effluent: petridish and pot, experiment No. 1 to 5
·         Sewage effluent: experiment No.6
·         Asbestos effluent:  experiment   No.7
·         Distillery effluent:   experiment No.8
·         Sewage and asbestos effluent:  experiment   No.9
·         Figures
·         Photoplates
79-136
79-97
97-105
105-113
114-119
120-122
123-128
129-132
CHAPTER V- Conclusion: Suggestions and Recommendations.
133-134
Annexure
135-136
II Part
137-232
Preface
138-140
CHAPTER I - Introduction:  legal provisions relating to environmental law.
141-150
CHAPTER II-Definitions of various terms, concepts and importance of compliance
 and enforcement and factors responsible for weaknesses of compliance and  enforcement.
151-164
CHAPTER III-Status highlights the problems of compliance and enforcement   in India.
165-180
CHAPTER IV -Judicial trend: views and directions of Supreme Court and High
Court decisions environmental compliance and enforcement effectiveness of
 environmental compliance and enforcement in polluting industries in India.
181-190
CHAPTER V-Effectiveness of environmental compliance and enforcement in Polluting Industry in India: a field survey.
191-198
CHAPTER VI -Conclusion: Suggestions and Recommendations.
199-210
 
 
Name of the Applicant: Dr. Amar Nath Giri Ex. Research Associate (IIM Lucknow & IGIDR Mumbai, Maharashtra)
Job Industrial/Instituional/research Experience: 12  Years
Father’s Name: Mr. Nageshwar Giri
Mother’s Name: Mrs. Kismati Devi
Date of Birth:   20-02-1978
Permanent Address: Rajendra Nagar (West) Gorakhnath Mandir 
                                          Gorakhpur, Uttar Pradesh
Telephone if any:       09912511918, 0552-2253437
 E-mail:                             amarnathgiri@nagarjunagroup.com, goswami248@gmail.com, goswami818@yahoo.com

PROFESSIONAL QUALIFICATION   

Ø  Ph.D. in Environmental Science from Lucknow University, Lucknow, in 2005, entitled “Environmental Impact of Industries on Agricultural crops and critical study of existing regulatory governance for most polluting Industries in India.” 
Ø  Ist Class M. Sc. in Environmental Science from Lucknow University in 1999.
Ø  Ist Class Post Graduate Diploma in Environmental Protection Law From Lucknow University, Lucknow in 2000.

 EDUCATIONAL QUALIFICATIONS

Ø  Ist Class B.Sc. (Z.B.C.) from Gorakhpur University in 1997.

Group: Environmental science, Management & law
  • Was a “ News Editor” of a monthly magazine on Environment and Health entitled “ The Green Trend” Lucknow.
  • Was an Environmental analyst at Mohan Meakin Ltd. Lucknow.
  • Was a Research Associate in I.I.M. Lucknow in Legal Management Group.
  • Was a Research Associate in I.I.M. Lucknow in Agricultural Management Center.
  • Worked as Research Associate in Environmental Division of Indira Gandhi Institute of Development Research, Mumbai.
PROJECTS /TRAINING UNDERTAKEN IN POLLUTION CONTROL:
Ø   Air pollution Assessment (Monitoring, Inventorisation & Modeling) at Delhi. Under Prof. V.K. Sharma, IGIDR Mumbai.

Nature of Job                                               

Job Details in Brief: This assignment focused on “Integrated Assessment of Air Quality at New Delhi.” The objective of this project is to assess the AQ at selected locations within New Delhi. The study was use an integrated approach including AQ Monitoring (Field Sampling and Laboratory Analysis), AQ Receptor Modelling (Source Identification i.e. SI and Apportionment i.e. SA) and empirical analysis of Health Impacts of AQ
Ø   State of Environment Report Maharashtra. Under Prof. V.K. Sharma, IGIDR Mumbai.
Ø  “Preperation for perspective plan for implementation of NFFWP at five district”. Under Professor Zabir Ali, Agriculture Management Centre IIM Lucknow.
Ø  “Environment Management  & Law in Industries.” Under Professor D.S. Sengar, Head legal Management group, IIM Lucknow.
Ø  “Synthesis of Urea and its impact on ornamental plants.” Site- I.F.F.C.O, Phulpur Allahabad. U.P. (India); Supervisor: Dr. B.D. Nautiyal, Reader Department of Botany, Lucknow University.
Ø  “Study the working Mechanism of C.E.T.P. (Operation & Maintenance) & analyze the Quality of water released from C.E.T.P. & E.T.P.” Training Programme: Common Effluent Treatment Plant  & Effluent treatment Plant in Unnao & Mohan Meakin.
Ø   “Impact of Basathrin pollution on reproductive potential of fresh water food fish         (Heteropneustes fossilis).” Department of Zoology, Lucknow University. Supervisor: Dr. S.P Trivedi, Reader Department of Zoology, Lucknow University.
Ø   “Evaluation of Noise Pollution in Lucknow city and its legal aspects.”Duratin- Three months, Guide; Prof. M.M. Lal, Ex.  Deputy Director, I.T.R.C.
TECHNIQUES KNOWN:
·        Operation and Maintenance of Effluent treatment plant ( Tanneres & Distillery)
·        Water analysis (i.e. BOD, COD, DO, EC, pH, alkalinity, heavy metal, metals, TDS, SS, TSS, total nitrogen, fluoride etc.).
  • Air Monitoring:
·  Meteorological data: Wind velocity, wind direction, temperature, relative humidity,
·  Particulate Matter: RSPM, TSPM. Gaseous pollutants: SOx, NOx. NH3, CO,
·  Chemical Species:  Metals, OC, EC.
·  Use of Air quality Model: CMB 8.2, FA-MR
  • Soil analysis (i.e. Organic matter, CaCO3, Ca, N, heavy metal & metals through DTPA extraction method, nitrogen, fluoride, Fe and P).
  • Petridish, soil, sand and hydroponics culture. 
  • Handling knowledge of UV spectrophotometer, AAS, EC, pH, centrifuges, spectrophotometer etc.
  • Estimation of enzymes especially – Amylase (Total, a and β), Catalase, Peroxidase, Acid phosphatage, SOD and IAA etc. in plants.
  • Osmotic relation in seed germination, relative water content (RWC), fresh weight, dry weight, moisture percentage.
  • SVI, GRI, LA, LAR, RGR
  • Estimation of pigments especially – Chlorophyll (a, b and total), Pheophytin (a, b and total) and total carotenoids.
  • Estimation of total protein, carbohydrate contents in plants.
  • Estimation of heavy metals and nutrients in plant tissue.
Paper published / communicated:
o   Giri Amar Nath, Srivastava, Dinesh Kumar and Trivedi, S.P. (2000). “Insecticide Basathrin Induced Histoanatomical Insult of ovarian tissue of Indian catfish, Heteropneustes fossilis.” Biological Memoirs 26 (1): 20-24.
Book: Ph.D thesis is Under Publication submitted in ICSSR Delhi.
Article:
o   “Living with the poison” The Green Trend (Environment and Health Investigative monthly magazine) September 2000.
o   “Khajuraho Temples” The Green Trend (Environment and Health Investigative monthly magazine) October 2000.
o   “Jute uses and processing” The Green Trend (Environment and Health Investigative monthly magazine) January 2001.
o   “Bombay Natural History Society” The Green Trend (Environment and Health Investigative monthly magazine) March& April 2001.
Booklets & Sheets:
o   “Biodiversity outlook, Significance& Conservation” (2002). The Green Trend Foundation Lucknow (U.P.)
o   “Environmental responsibilities”(2002). The Green Trend Foundation. Lucknow (U.P.)
o   “Air pollution “ an overview in Hindi (2002). The Green Trend Foundation. Lucknow (U.P.)
o   “Green News” An Enviro– News Sheet (Quarterly). The Green Trend Foundation. Lucknow (U.P.)
Industrial  visit:
Apart from theoretical knowledge of the subject , I am having  significant  exposure which have been gained by visiting  the following  industries.
Mohan Meakin Ltd. Lucknow, J.B. Daurala Paper Mills Sitapur, Shajhanpur Paper Mills, I.F.F.C.O. Phulpur Allahabad, F.C.I. G.K.P., WIMCO Barilly Camphor, Glass Industry, Tanneries, slaughter house Unnao. Oxygen Factory G.K.P., Sugar factory Nandganj Ghazipur etc.
Institutional /Board visit:
I.T.R.C, N.B.R.I., C.D.R.I, C.I.M.A.P., B.S.I.P., C.I.S.H., I.V.R.I., F.R.I, I.I.M.L., N.E.D.A, C.P.C.B., U.P.P.C.B., M.P.C.B. NPL, IIT Delhi, IEI Delhi, IIPA Delhi, IIT Bombay, TIFR, BARC, IGIDR etc.
Symposia /Seminar attended:
o   Paper presented in Poster session in Indian Science congress, (2002) Lucknow.
o   Was a delegate in Environment & health session, Indian Science  Congress, (2002) Lucknow.
o   Participated in the National Seminar on “Enhancement of Environmental status through Better management and Techniques.” Held at department of Botany, Lucknow University Lucknow.
o   One-day workshop on the state of Environment report sponsored by the World Bank and supported by department of environment and U.P. Pollution Control Board. Govt. of Uttar Pradesh held at Taj Hotel (2002).
o   Nutrient status, Needs and Recommendations for Major Fruit Crops of Uttar Pradesh Workshop held at CISH, Lucknow.
Achievements:
o   Worked in National service Scheme Two Years during my Graduation.
o   Was a College Champion in athletes at M.G.P.G. College Gorakhpur.
o   Was a President of Environmental Protection Student Association (E.P.S.A.) in 1998-2000. Lucknow University, Lucknow.
o   Act as a Volunteer in Indian Science Congress I2002, held at Lucknow University Lucknow.
o   Was an organizer of a number of campaigns, rally, seminar, plantations etc .viz:  “Controlled use of Polythene bags”, “Save drinking water”, Vehicular pollution control.” During my Post graduation.
o   Organised INDO-RUSSIAN Joint Seminar on “Institutional Reforms and Development Units in Transitional Economy” in collaboration with Russian Academy of Sciences, ICSSR under Indo-Russian Joint Commission for Cooperation in Social Sciences, IGIDR, Mumbai, February 12 & 13, 2007.
o   Was a Delegate in International Industrial relation Association  (IIRA) Asian Regional Congress on topic “ The Changing Global Labour Market – Challenges and Opportunities for Asia”  At  Hotel Ashok, New Delhi, India 19-21 April , 2007.
q  Represented District level Softball Championship held at HAL Lucknow.
q  Represented  (State level) Interuniversity Soft ball Championship held at Rohtak, Haryana 2000.
Computer Knowledge:
  • Geographical Information System (GIS) using GRASS and ARC/INFO Methods.
  • Dispersion Modelling of Air Pollutants using Guassion Plume Model.
  • Receptor Modelling of Air Pollutants using Statistical Techniques like Correlation and Regression, Chemical Mass Balance (CMB8), Factor Analysis‑Multiple Regression,  Composite Receptor Model, Cluster Analysis, etc.
  • Expertise to work on several computer softwares such as SPSS, MSOFFICE- Word, Excel, Power Point, Word Perfect, etc.
References :
o   Dr. V.K. Sharma  (Prof.), Environment Indira Gandhi Institute of Development Research, Mumbai. Mobile no. 9323121270
o   Dr. Y.K. Sharma (Reader) Botany Department, Lucknow University Lucknow. Mobile no. 09450359259
o   Dr. S.P. Trivedi   (Reader) Zoology Department, Lucknow University Lucknow. Mobile no.09415063431
o   Dr. B.K. Dube  (Senior Scientist) I.C.A.R.- Botany Department, Lucknow University Lucknow. Mobile no.09415469634
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  1. Description: C:\Documents and Settings\BOSE INSTITUTE\Desktop\images\image002.png
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    CENTENARY SESSION OF INDIAN SCIENCE CONGRESS
     3-7 JANUARY, 2013, KOLKATA
    Annual Session of Indian Science Congress has emerged as a major national event. The centenary session scheduled for 3rd – 7th January, 2013 gains historical importance in more than one way. Whereas the themes for all the sessions up the period of 2003 since the first session in 1914 could be grouped under ‘Shaping of the Indian Science’, the theme selected for the centenary session is “Science for shaping the future of India”.
    Webcast Link
    Photo Gallery
    Video Uploads
    Speeches and Lectures
    §  Address of Hon'ble President of India at the Inauguration
    §  प्रधानमंत्री द्वारा भारतीय विज्ञान कांग्रेस के शताब्‍दी अधिवेशन में विज्ञान प्रौद्योगिकी और नवोन्‍मेष नीति, 2013 प्रस्‍तुत
    §  Adress of the Hon'ble Minister for Science and Technology and Earth Sciences at the Inauguration of Children Science Congress on 4th January 2013
    §  The Key features of the STI policy 2013
    Newspaper Clippings

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  3. What is the difference between Nm3 and Sm3?

    Unfortunately neither Nm3 (normal cubic meter) or Sm3 (standard cubic meter) are complete definitions in themselves. It is essential to know the standard reference conditions of temperature and pressure to define the gas volume since there are various debates about what normal and standard should be.

    Most commonly used reference conditions are:
    Normal cubic meter (Nm3) - Temperature: 0 °C, Pressure: 1.01325 barA
    Standard cubic meter (Sm3) - Temperature: 15 °C, Pressure: 1.01325 barA

    barA: absolute pressure

    How do I calculate Nm3 and Sm3 and what is the conversion rate?

    The volume of gases changes with temperature and pressure, therefore these parameters are also part of the conversion equation.

    The conversion from Sm3 to Nm3:

    V1/V2 = (P2xT1) / (P1xT2)
    V1/V2 = (288.16x1.013) / (273.16x1.013) = 1.05491287

    Temperature is entered in K; 273.16 is absolute zero
    Interpretation: 1Nm3 is 5,49% larger than Sm3, 1Nm3>1Sm3

    Some of our competitors use 15°C and 981mBar as reference conditions for standard cubic meter. The calculation is following:

    V1/V2 = (288.16x1.013) / (273.16x0.981) = 1.08932389

    Interpretation: 1Nm3 is 8,9% larger than Sm3. It also means the stated capacity of the generator stated in Nm3/h is 8.9% larger than same capacity defined in Sm3/h.
    Assumption: It is essential to consider these facts when projecting the gas generating system or when actually making decision to purchase certain model because you might be actually buying less than you actually think you are.
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  5. It's total shutdown in Seemandhra

    TNN | Oct 5, 2013, 06.38 AM IST

    It's total shutdown in Seemandhra
    Normal life came to a grinding halt in all the 13 districts of Seemandhra with people voluntarily observing a complete shutdown in protest against the Union cabinet’s decision to create Telangana.

    VIJAYAWADA/VISAKHAPATNAM: Normal life came to a grinding halt in all the 13 districts of Seemandhra with people voluntarily observing a complete shutdown in protest against the Union cabinet's decision to create Telangana. The bandh was marred by sporadic incidents of attacks on private vehicles, Congress offices, railway stations and a couple of other government properties in some districts.

    Traffic between southern and northern parts of India was badly hit as Samaikyandhra protesters squatted on national highways, burnt tyres on arterial roads and prevented movement of vehicles on Chennai-Kolkata, Machilipatnam-Pune, Kondapalli-Jagdalpur, Bangalore-Hyderabad, and Tirupati-Chennai highways. Many private vehicles, especially two-wheelers were set on fire by protesters in Vijayawada, Vizianagaram and Anantapur.

    All government and private offices, petrol bunks, banks, educational institutions, ATMs, and cinema halls remained closed for the day. While the APNGO Association has called for a two-day bandh, the YSRCP announced that it will shutdown Seemandhra for 72 hours. Power generation at Vijayawada thermal power station was affected as employees refused to attend to duties and did not allow any technical snags to be rectified.

    Tension mounted in Visakhapatnam, Vijayawada, and Anantapur as activists of TDP and YSRCP clashed with each other in a bid to woo the public. Protests have been going on in Seemandhra region for the past two months causing heavy loss to the state exchequer.

    Congress offices were attacked at Dhone in Kurnool district and Kakinada in East Godavari district. In Tirupati the agitators stopped power supply to the residence of local MP Chinta Mohan. Pilgrims suffered in Tirupati as RTC buses and private vehicles were stopped between Tirupati and Tirumala. The bandh is likely to cast a shadow on the Brahmotsavams in Tirumala and Dasara festivities at Sri Kanakadurga temple in Vijayawada.

    With the protesters staging rasta rokos separately on highways, the vehicular movement on the national highways was badly hit. According to reports, national highways were blocked in Vijayawada, Guntur, Ongole, Nellore, Rajahmundry, Eluru, Visakhapatnam, Kurnool, Kadapa, Anantapur, and Srikakulam.

    Private vehicles, which have been shuttling between district headquarters ever since APSRTC buses went off roads about 50 days ago, joined the agitation as well. Chaos prevailed at government hospitals as doctors joined the strike. Doctors in many places refused to attend to outpatient services.

    Tension prevailed in Tenali when local TDP activists made a vain bid to barge into assembly speaker Nadendla Manohar's residence. Police caned and dispersed the agitators. Meanwhile, CRPF personnel chased protesters when they entered the ONGC drilling site near Chakalipalem in East Godavari district.

    In Chittoor, activists attacked the buses of Diwakar travels owned by Congress legislator JC Diwakar Reddy. In Guntur TDP activists attacked district Congress party office and broke windowpanes. TDP activists staged dharna in front of the residence of agriculture minister Kanna Lakshminarayana in Guntur demanding his resignation.
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  7. Chemical Solutions

    How to Make a Chemical Solution

    By Anne Marie Helmenstine, Ph.D.,

    Volumetric flasks are used to accurately prepare solutions for chemistry.
    Volumetric flasks are used to accurately prepare solutions for chemistry.
    This is how to make a chemical solution using a solid dissolved in a liquid, such as water or alcohol. If you don't need to be very accurate, you can use a beaker or Erlenmeyer flask to prepare a solution. More often, you'll use a volumetric flask to prepare a solution so that you'll have a known concentration of solute in solvent.

    1. Weigh out the solid that is your solute.
    2. Fill the volumetric flask about halfway with distilled water or deionized water (aqueous solutions) or other solvent.
    3. Transfer the solid to the volumetric flask.
    4. Rinse the weighing dish with the water to make certain all of the solute is tranferred into the flask.
    5. Stir the solution until the solute is dissolved. You may need to add more water (solvent) or apply heat to dissolve the solid.
    6. Fill the volumetric flask to the mark with distilled or deionized water.
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  8. Concentration and Molarity Worked Example Problem

    Preparing a Stock Solution

    By Anne Marie Helmenstine, Ph.D.,
    Question: a) Explain how to prepare 25 liters of a 0.10 M BaCl2 solution, starting with solid BaCl2.
    b) Specify the volume of the solution in (a) needed to get 0.020 mol of BaCl2.
    Solution:
    Part a): Molarity is an expression of the moles of solute per liter of solution, which can be written:
    molarity (M) = moles solute / liters solution
    Solve this equation for moles solute:
    moles solute = molarity × liters solution
    Enter the values for this problem:
    moles BaCl2 = 0.10 mol/liter × 25 liter
    moles BaCl2 = 2.5 mol
    To determine how many grams of BaCl2 are needed, calculate the weight per mole. Look up the atomic masses for the elements in BaCl2 from the Periodic Table. The atomic masses are found to be:
    Ba = 137
    Cl = 35.5
    Using these values:
    1 mol BaCl2 weighs 137 g + 2(35.5 g) = 208 g
    So the mass of BaCl2 in 2.5 mol is:
    mass of 2.5 moles of BaCl2 = 2.5 mol × 208 g / 1 mol
    mass of 2.5 moles of BaCl2 = 520 g
    To make the solution, weigh out 520 g of BaCl2 and add water to get 25 liters.
    Part b): Rearrange the equation for molarity to get:
    liters of solution = moles solute / molarity
    In this case:
    liters solution = moles BaCl2 / molarity BaCl2
    liters solution = 0.020 mol / 0.10 mol/liter
    liters solution = 0.20 liter or 200 cm3
    Answer
    Part a). Weigh out 520 g of BaCl2. Stir in sufficient water to give a final volume of 25 liters.
    Part b). 0.20 liter or 200 cm3
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  9. Calculating Concentration

    Concentration Units & Dilutions

    By Anne Marie Helmenstine, Ph.D.,

    • Do the units of calculation confuse you?
    Do the units for solution concentration confuse you? Get definitions and examples for calculating percent composition by mass, mole fraction, molarity, molality, and normality.
    The concentration of a chemical solution refers to the amount of solute that is dissolved in a solvent. We normally think of a solute as a solid that is added to a solvent (e.g., adding table salt to water), but the solute could just as easily exist in another phase. For example, if we add a small amount of ethanol to water, then the ethanol is the solute and the water is the solvent. If we add a smaller amount of water to a larger amount of ethanol, then the water could be the solute!

    Units of Concentration
    Once you have identified the solute and solvent in a solution, you are ready to determine its concentration. Concentration may be expressed several different ways, using percent composition by mass, volume percent, mole fraction, molarity, molality, or normality.
    1. Percent Composition by Mass (%) This is the mass of the solute divided by the mass of the solution (mass of solute plus mass of solvent), multiplied by 100.
      Example:
      Determine the percent composition by mass of a 100 g salt solution which contains 20 g salt.
      Solution:
      20 g NaCl / 100 g solution x 100 = 20% NaCl solution
    2. Volume Percent (% v/v) Volume percent or volume/volume percent most often is used when preparing solutions of liquids. Volume percent is defined as:
      v/v % = [(volume of solute)/(volume of solution)] x 100%
      Note that volume percent is relative to volume of solution, not volume of solvent. For example, wine is about 12% v/v ethanol. This means there are 12 ml ethanol for every 100 ml of wine. It is important to realize liqud and gas volumes are not necessarily additive. If you mix 12 ml of ethanol and 100 ml of wine, you will get less than 112 ml of solution.
      As another example. 70% v/v rubbing alcohol may be prepared by taking 700 ml of isopropyl alcohol and adding sufficient water to obtain 1000 ml of solution (which will not be 300 ml).
    3. Mole Fraction (X) This is the number of moles of a compound divided by the total number of moles of all chemical species in the solution. Keep in mind, the sum of all mole fractions in a solution always equals 1.
      Example:
      What are the mole fractions of the components of the solution formed when 92 g glycerol is mixed with 90 g water? (molecular weight water = 18; molecular weight of glycerol = 92)
      Solution:
      90 g water = 90 g x 1 mol / 18 g = 5 mol water
      92 g glycerol = 92 g x 1 mol / 92 g = 1 mol glycerol
      total mol = 5 + 1 = 6 mol
      xwater = 5 mol / 6 mol = 0.833
      x glycerol = 1 mol / 6 mol = 0.167
      It's a good idea to check your math by making sure the mole fractions add up to 1:
      xwater + xglycerol = .833 + 0.167 = 1.000
    4. Molarity (M) Molarity is probably the most commonly used unit of concentration. It is the number of moles of solute per liter of solution (not necessarily the same as the volume of solvent!).
      Example:
      What is the molarity of a solution made when water is added to 11 g CaCl2 to make 100 mL of solution?
      Solution:
      11 g CaCl2 / (110 g CaCl2 / mol CaCl2) = 0.10 mol CaCl2
      100 mL x 1 L / 1000 mL = 0.10 L
      molarity = 0.10 mol / 0.10 L
      molarity = 1.0 M
    5. Molality (m) Molality is the number of moles of solute per kilogram of solvent. Because the density of water at 25°C is about 1 kilogram per liter, molality is approximately equal to molarity for dilute aqueous solutions at this temperature. This is a useful approximation, but remember that it is only an approximation and doesn't apply when the solution is at a different temperature, isn't dilute, or uses a solvent other than water.
      Example:
      What is the molality of a solution of 10 g NaOH in 500 g water?
      Solution:
      10 g NaOH / (40 g NaOH / 1 mol NaOH) = 0.25 mol NaOH
      500 g water x 1 kg / 1000 g = 0.50 kg water
      molality = 0.25 mol / 0.50 kg
      molality = 0.05 M / kg
      molality = 0.50 m
    6. Normality (N) Normality is equal to the gram equivalent weight of a solute per liter of solution. A gram equivalent weight or equivalent is a measure of the reactive capcity of a given molecule. Normality is the only concentration unit that is reaction dependent.
      Example:
      1 M sulfuric acid (H2SO4) is 2 N for acid-base reactions because each mole of sulfuric acid provides 2 moles of H+ ions. On the other hand, 1 M sulfuric acid is 1 N for sulfate precipitation, since 1 mole of sulfuric acid provides 1 mole of sulfate ions.
    Dilutions
    You dilute a solution whenever you add solvent to a solution. Adding solvent results in a solution of lower concentration. You can calculate the concentration of a solution following a dilution by applying this equation:
    MiVi = MfVf
    where M is molarity, V is volume, and the subscripts i and f refer to the initial and final values.
    Example:
    How many millilieters of 5.5 M NaOH are needed to prepare 300 mL of 1.2 M NaOH?
    Solution:
    5.5 M x V1 = 1.2 M x 0.3 L
    V1 = 1.2 M x 0.3 L / 5.5 M
    V1 = 0.065 L
    V1 = 65 mL
    So, to prepare the 1.2 M NaOH solution, you pour 65 mL of 5.5 M NaOH into your container and add water to get 300 mL final volume.
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  11. What is the Difference Between Molarity and Normality?

    Molarity vs Normality


    Both molarity and normality are measures of concentration. One is a measure of the number of moles per liter of solution and the other changes depending on the solution's role in the reaction.

    Molarity is the most commonly used measure of concentration. It is expressed as the number of moles of solute per liter of solution.

    A 1 M solution of H2SO4 contains 1 mole of H2SO4 per liter of solution.

    H2SO4 dissociates into H+ and SO4- ions in water. For every mole of H2SO4 that dissociates in solution, 2 moles of H+ and 1 mole of SO4- ions are formed. This is where normality is generally used.

    Normality is a measure of concentration that is equal to the gram equivalent weight per liter of solution. Gram equivalent weight is a measure of the reactive capacitity of a molecule.

    The solution's role in the reaction determines the solution's normality.

    For acid reactions, a 1 M H2SO4 solution will have a normality (N) of 2 N because 2 moles of H+ ions are present per liter of solution.

    For sulfide precipitation reactions, where the SO4- ion is the important part, the same 1 M H2SO4 solution will have a normality of 1 N.
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  12. Density, Specific Weight and Specific Gravity

    An introduction and definition of density, specific weight and specific gravity - formulas with examples

    Density

    Density is defined as an objects mass per unit volume. Mass is a property.
    • Mass and Weight - the Difference! - What is weight and what is mass? An explanation of the difference between weight and mass.
    The density can be expressed as
    ρ = m / V = 1 / vg         (1)
    where
    ρ = density (kg/m3)
    m = mass (kg)
    V = volume (m3)
    vg = specific volume (m3/kg)
    The SI units for density are kg/m3. The imperial (U.S.) units are lb/ft3 (slugs/ft3). While people often use pounds per cubic foot as a measure of density in the U.S., pounds are really a measure of force, not mass. Slugs are the correct measure of mass. You can multiply slugs by 32.2 for a rough value in pounds.
    The higher the density, the tighter the particles are packed inside the substance. Density is a physical
    property constant at a given temperature and density can help to identify a substance.

    Relative Density  (Specific Gravity)

    Relative density of a substance is the ratio of the substance to the density of water at 4oC, i.e.
    Substance Relative density
    Acetylene 0.0017
    Air, dry 0.0013
    Alcohol 0.82
    Aluminum 2.72
    Brass 8.48
    Cadmium 8.57
    Chromium 7.03
    Copper 8.79
    Carbon dioxide 0.00198
    Carbon monoxide 0.00126
    Cast iron 7.20
    Hydrogen 0.00009
    Lead 11.35
    Mercury 13.59
    Nickel 8.73
    Nitrogen 0.00125
    Nylon 1.12
    Oxygen 0.00143
    Paraffin 0.80
    Petrol 0.72
    PVC 1.36
    Rubber 0.96
    Steel 7.82
    Tin 7.28
    Zinc 7.12
    Water (4oC) 1.00
    Water, sea 1.02

    Example - Use the Density to Identify the Material:

    An unknown liquid substance has a mass of 18.5 g and occupies a volume of 23.4 ml. (milliliter).
    The density can be calculated as
    ρ = [(18.5 g) / (1000 g/kg)] / [(23.4 ml) / (1000 ml/l) (1000 l/m3)]
        = (18.5 10-3 kg) / (23.4 10-6 m3)
        = 790 (kg/m3)
    If we look up densities of some common substances, we can find that ethyl alcohol, or ethanol, has a density of 790 kg/m3. The liquid may be ethyl alcohol!

    Example - Use Density to Calculate the Mass of a Volume

    The density of titanium is 4507 kg/m3. Calculate the mass of 0.17 m3 titanium!
    m = (0.17 m3) (4507 kg/m3)
        = 766.2 (kg)

    Specific Weight

    Specific Weight is defined as weight per unit volume. Weight is a force.
    • Mass and Weight - the difference! - What is weight and what is mass? An explanation of the difference between weight and mass.
    Specific Weight can be expressed as
    γ = ρ g         (2)
    where
    γ = specific weight (N/m3)
    ρ = density (kg/m3)
    g = acceleration of gravity (m/s2)
    The SI-units of specific weight are N/m3. The imperial units are lb/ft3. The local acceleration g is under normal conditions 9.807 m/s2 in SI-units and 32.174 ft/s2 in imperial units.

    Example - Specific Weight Water

    Specific weight for water at 39 oF (4 oC) is 62.4 lb/ft3 (9.81 kN/m3) in imperial units. Specific weight in SI units can be calculated like
    γ = (1000 kg/m3) (9.81 m/s2)
        = 9810 (N/m3)
        = 9.81 (kN/m3)

    Example - Specific Weight Some other Materials

    Product Specific Weight - γ
    Imperial Units
    (lb/ft3)    		 SI Units
    (kN/m3)
    Aluminium 172 27
    Brass 540 84.5
    Copper 570 89
    Ethyl Alcohol 49.3 7.74
    Gasoline 42.5 6.67
    Glycerin 78.6 12.4
    Mercury 847 133.7
    SAE 20 Oil 57 8.95
    Seawater 64 10.1
    Stainless Steel 499 - 512 78 - 80
    Water 62.4 9.81
    Wrought Iron 474 - 499 74 - 78

    Specific Gravity (Relative Density)

    Specific Gravity Liquids

    The Specific Gravity - SG - of a liquid is a dimensionless unit defined as the ratio of density of the liquid to the density of water at a specified temperature. Specific Gravity of a liquid can be expressed
    SG = ρ / ρH2O         (3)
    where
    SG = specific gravity
    ρ = density of fluid or substance (kg/m3)
    ρH2O = density of water (kg/m3)
    It is common to use the density of water at 4 oC (39oF) as reference - at this point the density of water is at the highest - 1000 kg/m3 or 62.4 lb/ft3.

    Since Specific Weight is dimensionless it has the same value in the metric SI system as in the imperial English system (BG). At the reference point the Specific Gravity has same numerically value as density.

    Example - Specific Gravity

    If the density of iron is 7850 kg/m3, 7.85 grams per cubic centimeter (cm3), 7.85 kilograms per liter, or 7.85 metric tons per cubic meter - the specific gravity of iron is:
    SG = (7850 kg/m3) / (1000 kg/m3)
        = 7.85
    • water density is 1000 kg/m3

    Specific Gravity Gases

    The Specific Gravity - SG - of a gas is a dimensionless unit defined as the ratio of density of the gas to the density of air at a specified temperature and pressure. In general conditions according NTP - Normal Temperature and Pressure - defined as air at 20oC (293.15 K, 68oF) and 1 atm ( 101.325 kN/m2, 101.325 kPa, 14.7 psia, 0 psig, 30 in Hg, 760 torr), where density of air is 1.205 kg/m3 is used.
    Specific Gravity of a gas can be expressed
    SG = ρ / ρair         (3)
    where
    SG = specific gravity
    ρ = density of gas or substance (kg/m3)
    ρair = density of air (kg/m3)
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  13. Phytoremediation
    What is phytoremediation?
    The word's etymology comes from the Greek φυτο (phyto) = plant, and Latin «remedium» = restoring balance, or remediating.
    Phytoremediation consists in depolluting contaminated soils, water or air with plants able to contain, degrade or eliminate metals, pesticides, solvents, explosives, crude oil and its derivatives, and various other contaminants, from the mediums that contain them.
    It is clean, efficient, inexpensive and non-environmentally disruptive, as opposed to processes that require excavation of soil.
    Overview:
    Phytoremediation is the use of certain plants to clean up soil, sediment, and water contaminated with metals and/or organic contaminants such as crude oil, solvents, and polyaromatic hydrocarbons (PAHs).
    Phytoremediation is the use of green plants to remove, contain, or render harmless environmental contaminants. It is a promising technology that addresses clean-up of organic solvents, PCBs, heavy metals, polyaromatic hydrocarbons, explosives and energetics, or nutrients.
    It is a name for the expansion of an old process that occurs naturally in ecosystems as both inorganic and organic constituents cycle through plants.
    Plant physiology, agronomy, microbiology, hydrogeology, and engineering are combined to select the proper plant and conditions for a specific site.
    Phytoremediation is an aesthetically pleasing mechanism that can reduce remedial costs, restore habitat, and clean up contamination in place rather than entombing it in place or transporting the problem to another site.
    The key physiological processes in phytoremediation include:
    a.     Stimulation of microorganism-based transformation by plant exudates and leachates, and by fluctuating oxygen regimes
    b.    Slowing of contaminant transport from the vegetated zone due to adsorption and increased evapotranspiration
    c.     Plant uptake, followed by metabolism or accumulation
    Various phytoremediation processes
    Phytoextraction - uptake and concentration of substances from the environment into the plant biomass.
    Phytostabilization - reducing the mobility of substances in the environment, for example by limiting the leaching of substances from the soil.
    Phytotransformation - chemical modification of environmental substances as a direct result of plant metabolism, often resulting in their inactivation, degradation (phytodegradation) or immobilization (phytostabilization).
    Phytostimulation - enhancement of soil microbial activity for the degradation of contaminants, typically by organisms that associate with roots. This process is also known as rhizosphere degradation.
    Phytovolatilization - removal of substances from soil or water with release into the air, sometimes as a result of phytotransformation to more volatile and / or less polluting substances.
    Rhizofiltration - filtering water through a mass of roots to remove toxic substances or excess nutrients. The pollutants remain absorbed in or adsorbed to the roots.
    a.    Phytoextraction
    Phytoextraction (or phytoaccumulation) uses plants to remove contaminants from soils, sediments or water into harvestable plant biomass.
    Phytoextraction has been growing rapidly in popularity world-wide for the last twenty years or so. Generally this process has been tried more often for extracting heavy metals than for organics. At the time of disposal contaminants are typically concentrated in the much smaller volume of the plant matter than in the initially contaminated soil or sediment.
    'Mining with plants', or phytomining, is also being experimented with.
    The plants absorb contaminants through the root system and store them in the root biomass and/or transport them up into the stems and/or leaves. A living plant may continue to absorb contaminants until it is harvested. After harvest a lower level of the contaminant will remain in the soil, so the growth/harvest cycle must usually be repeated through several crops to achieve a significant cleanup. After the process, the cleaned soil can support other vegetation.
    Two versions of phytoextraction:
    a) natural hyper-accumulation, where plants naturally take up the contaminants in soil unassisted, and b) induced or assisted hyper-accumulation, in which a conditioning fluid containing a chelator or another agent is added to soil to increase metal solubility or mobilization so that the plants can absorb them more easily.
    Examples of phytoextraction from soils:
    Arsenic, using the Sunflower (Helianthus annuus), or the Chinese Brake fern (Pteris spp), a hyperaccumulator. Chinese Brake fern stores arsenic in its leaves.
    Cadmium and zinc, using alpine pennycress (Thlaspi caerulescens), a hyperaccumulator of these metals at levels that would be toxic to many plants. On the other hand, the presence of copper seems to impair its growth.
    Lead, using Indian Mustard (Brassica juncea), Ragweed (Ambrosia artemisiifolia), Hemp Dogbane (Apocynum cannabinum), or Poplar trees, which sequester lead in its biomass.
    Salt-tolerant (moderately halophytic) barley and/or sugar beets are commonly used for the extraction of Sodium chloride (common salt) to reclaim fields that were previously flooded by sea water.
    Uranium, using sunflowers, as used after the Chernobyl accident.
    Mercury, selenium and organic pollutants such as polychlorinated biphenyls (PCBs) have been removed from soils by transgenic plants containing genes for bacterial enzymes.
    b.    Phytostabilization
    Phytostabilization focuses on long-term stabilization and containment of the pollutant.
    For example, the plant's presence can reduce wind erosion, or the plant's roots can prevent water erosion, immobilize the pollutants by adsorption or accumulation, and provide a zone around the roots where the pollutant can precipitate and stabilize.
    Unlike phytoextraction, phytostabilization mainly focuses on sequestering pollutants in soil near the roots but not in plant tissues. Pollutants become less bioavailable and livestock, wildlife, and human exposure is reduced. An example application of this sort is using a vegetative cap to stabilize and contain mine tailings.
    c.     Phytotransformation
    In the case of organic pollutants, such as pesticides, explosives, solvents, industrial chemicals, and other xenobiotic substances, certain plants, such as Cannas, render these substances non-toxic by their metabolism. In other cases, microorganisms living in association with plant roots may metabolize these substances in soil or water.
    These complex and recalcitrant compounds cannot be broken down to basic molecules (water, carbondioxide, etc) by plant molecules, and hence the term phytotransformation represents a change in chemical structure without complete breakdown of the compound.
    The term "Green Liver Model" is used to describe phytotransformation, as plants behave similar to the human liver when dealing with these xenobiotic compounds (foreign compound/pollutant). After uptake of the xenobiotics, plant enzymes increase the polarity of the xenobiotics by adding functional groups such as hydroxyl groups (-OH).
    This is known as Phase I metabolism, similar to the way the human liver increases the polarity of drugs and foreign compounds (Drug Metabolism). While in the human liver, enzymes like Cytochrome P450s are responsible for the initial reactions, in plants enzymes such as nitroreductases carry out the same role.
    In the second stage of phytotransformation, known as Phase II metabolism, plant biomolecules such as glucose and amino acids are added to the polarized xenobiotic to further increase the polarity (known as conjugation). This is again similar to the processes occurring in the human liver wherein glucuronidation (addition of glucose molecules by the UGT (e.g. UGT1A1) class of enzymes) and glutathione addition reactions occur on reactive centers of the xenobiotic.
    Phase I and II reactions serve to increase the polarity and reduce the toxicity of the compounds, although many exceptions to the rule are seen at least in the case of the human liver. The increased polarity also allows for easy transport of the xenobiotic along aqueous channels.
    In the final stage of phytotransformation (Phase III metabolism), a sequestration of the xenobiotic occurs within the plant. The xenobiotics polymerize in a lignin-like manner and get a complex structure which is sequestered in the plant. This ensures that the xenobiotic is safely stored in the plant, and does not affect the functioning of the plant.
    However, preliminary studies have shown that these plants can be toxic to small animals (such as snails) and hence plants involved in phytotransformation may need to be maintained in a closed enclosure.
    The human liver differs from plants in Phase III metabolism, since the liver can transport the xenobiotics into the bile for eventual excretion. Since plants have no excretory mechanisms, they sequester the modified xenobiotics.
    Hence, the plants reduce toxicity (with exceptions) and sequester the xenobiotics in phytotransformation. Trinitrotoluene (TNT) phytotransformation has been extensively researched and a transformation pathway has been proposed.
    Advantages and limitations
    Advantages:
    ü the cost of the phytoremediation is lower than that of traditional processes both in situ and ex situ
    ü the plants can be easily monitored
    ü the possibility of the recovery and re-use of valuable metals (by companies specializing in “phytomining”)
    ü it is the least harmful method because it uses naturally occurring organisms and preserves the natural state of the environment.
    Limitations:
    ü phytoremediation is limited to the surface area and depth occupied by the roots.
    ü slow growth and low biomass require a long-term commitment
    ü with plant-based systems of remediation, it is not possible to completely to prevent the leaching of contaminants into the groundwater (without the complete removal of the contaminated ground which in itself does not resolve the problem of contamination)
    ü the survival of the plants is affected by the toxicity of the contaminated land and the general condition of the soil.
    ü possible bio-accumulation of contaminants which then pass into the food chain, from primary level consumers upwards.
    Advantages and Disadvantages of Phytoremediation
    When using phytoremediation there are many positive and negative aspects to consider. The advantages and disadvantages are listed below.
    Advantages
    Disadvantages
    ü Works on a variety on organic and inorganic compounds
    ü Can be either In Situ/ Ex Situ
    ü Easy to implement and maintain
    ü Low-cost compared to other treatment methods
    ü Environmentally Friendly and aesthetically pleasing to the public
    ü Reduces the amount wastes to be landfilled
    ü May take several years to remediate
    ü May depend on climatic conditions
    ü Restricted to sites with shallow contamination within rooting zone
    ü Harvested biomass from phytoextraction may be classified as a RCRA hazardous waste
    ü Consumption of contaminated plant tissue is also a concern
    ü Possible effect on the food chain
    A major advantage that is listed above is the low cost. For example, the cost of cleaning up one acre of sandy loam soil at a depth of 50cm with plants is estimated at $60,000-$100,000 compared to $400,000 for the conventional excavation and disposal method. One reason for this low cost is phytoremediation may not require expensive equipment or highly specialized personnel, and can be relatively easy to implement.
    One major concern with phytoremediation is the possible affects on the food chain. For example vegetation is used that absorbs toxic or heavy metals and moles or voles eat the metal contaminated plants. The predators of the moles or voles then become victims of intoxication. All though the possibilities of such scenarios are being looked at, more fieldwork and analysis is necessary to understand the possible effects phytoremediation can have.
    Hyperaccumulators and biotic interactions
    A plant is said to be a hyperaccumulator if it can concentrate the pollutants in a minimum percentage which varies according to the pollutant involved (for example: more than 1000 mg/kg of dry weight for nickel, copper, cobalt, chromium or lead; or more than 10,000 mg/kg for zinc or manganese.
    Most of the 215 metal-hyperaccumulating species included in their review hyperaccumulate nickel. They listed 145 hyperaccumulators of nickel (around 300 Ni accumulators are known, 26 of cobalt, 24 of copper, 14 of zinc, four of Lead, and two of Chromium.
    This capacity for accumulation is due to hypertolerance, or phytotolerance: the result of adaptative evolution from the plants to hostile environments along multiple generations.
    Boyd and Martens list 4 biotic interactions that may be affected by metal hyperaccumulation, to which can be added the biofilm as a particular aspect of micorrhizae:
    a.    Protection
    More and more evidence show that the metals in hyperaccumulating plants give them some protection from various bacteria, fungi and/or insects.
    For instance, with foliar Ni concentrations as low as 93 mg/kg, the larval weight of Spodoptera exigua (Lepidoptera: Noctuidae) (beet army worm) is reduced and time to pupation extended.
    Published research supporting the hypothesis of metal hyperaccumulation:
    Researcher
    Plant species
    Metal
    Organism(s) affected
    Ernst 1987
    Silene vulgaris (Moench) Garke
    Cu (400 mg g-¹)
    Hadena cucubalis Schiff. (Lepidoptera: Noctuidae)
    Boyd et al. 1994
    Streptanthus polygaloides Gray
    Ni
    Xanthomonas campestris (Gram-negative bacterium)
    Boyd et al. 1994
    Streptanthus polygaloides Gray
    Ni
    Alternaria brassicicola (Imperfect fungus)
    Boyd et al. 1994
    Streptanthus polygaloides Gray
    Ni
    Erisyphe polygoni (Powdery mildew)
    Martens & Boyd 1994
    Streptanthus polygaloides
    Ni
     (Lepidoptera: Pieridae)
    Boyd & Martens 1994
    Thlaspi montanum L. var. montanum
    Ni
    Pieris rapae
    Pollard & Baker 1997
    Thlaspi caerulescens J. and C. Presl.
    Zn
    Schistocerca gregaria (Forsk.) (Orthoptera: Acrididae)
    Pollard & Baker 1997
    Thlaspi caerulescens J. and C. Presl.
    Zn
    Deroceras carvanae (Pollonera) (Pulmonata: Limacidae)
    Pollard & Baker 1997
    Thlaspi caerulescens J. and C. Presl.
    Zn
    Pieris brassicae L. (Lepidoptera: Pieridae)
                
                                         
    The defense against viruses is not always supported. Davis et al. (2001) have compared two close species S. polygaloides Gray (Ni hyperaccumulator) and S. insignis Jepson (non-accumulator), inoculating them with Turnip mosaic virus. They showed that the presence of nickel weakens the plant's response to the virus.
    Circumvention of plants' elemental defences by their predators may occur in three ways:
    (1) selective feeding on low-metal tissues,
    (2) use of a varied diet to dilute metal-containing food (likely more efficient in large-sized herbivores), and
    (3) tolerance of high dietary metal content.
    Avoidance of an elemental defence via selective feeding:
    Mishra & Kar (1974) reported nickel to be transported through the xylem of crop plants. Similarly, Kramer et al. (1996) showed that Ni is transported as a complex with the amino-acid histidine in the xylem. This implies that phloem fluid may contain little nickel; thus phloem fluid may be used by able organisms as a rich source of carbohydrates.
    Pea aphids (Acyrthosiphon pisum [Harris]; Homoptera: Aphididae) feeding on Streptanthus polygaloides Gray (Brassicaceae) have equal survival and reproduction rates for plants containing ca. 5000 mg/kg nickel amended with NiCl2, and those containing 40 mg/kg nickel. This means that either the phloem fluid is poor in nickel even for nickel hyperaccumulators, or that the aphids tolerate nickel.
    Moreover the aphids feeding on high nickel-content plants only show a small increase of nickel content in their bodies, relatively to the nickel content of aphids feeding on low-nickel plants. On the other hand, aphids (Brachycaudus lychnidis L.) fed on the zinc-tolerant plant Silene vulgaris (Moench) Garcke (Caryophyllaceae) - which can contain up to 1400 mg/kg zinc in its leaves – were reported showing elevated (9000 mg/kg) zinc in their bodies.
    Metal tolerance
    Hopkin (1989) and Klerks (1990) demonstrated it for animal species; Brown & Hall (1990) for fungal species; and Schlegel & al. (1992) and Stoppel & Schlegel (1995) for bacterial species.
    Plants of Streptanthus polygaloides (Brassicaceae, Ni hyperaccumulator) can be parasited by Cuscuta californica var. breviflora Engelm. (Cuscutaceae). Metal contents of Cuscuta ranged from 540–1220 mg/kg Ni, 73-fold higher than the metal contents of Cuscuta parasitizing a co-occurring non-hyperaccumulator plant species.
    Cuscuta plants are therefore very Ni-tolerant - 10 mg Ni/kg is sufficient for growth to start decreasing in unadapted plants. According to Boyd & Martens (subm.) this is "the first well-documented instance of the transfer of elemental defences from a hyperaccumulating host to a seed plant parasite".
    b.    Interferences with neighbour plants of different species
    Its likelihood between hyperaccumulators and neighbouring plants was suggested but no mechanism was proposed. Gabrielli et al. (1991), and Wilson & Agnew (1992), suggested a decrease in competition experienced by the hyperaccumulators for the litterfall from hyperaccumulators' canopy.
    This mechanism mimics allelopathy in its effects, although technically due to redistribution of an element in the soil rather than to the plant manufacturing an organic compound. Boyd et Martens call it ‘‘elemental allelopathy’’ - without the autoxicity problem met in other types of allelopathy (Newman 1978).
    c.     Mutualism
    Two types of mutualism are considered here, mycorrhizal associations or mycorrhizae, and animal-mediated pollen or seed dispersal.
    1 - Mycorrhizal associations or mycorrhizae
    There are two types of mycorrhizal fungi: ectomycorrhizae and endomycorrhizae. Ectomycorrhizae form sheaths around plant roots, endomycorrhizae enter cortex cells in the roots.
    Mycorrhizae are the symbiotic relationship between a soil-borne fungus and the roots of a plant. Some hyperaccumulators may form mycorrhizae and, in some cases, the latter may have a role in metal treatment.
    In soils with low metal levels, vesicular arbuscular mycorrhizae enhance metal uptake of non-hyperaccumulating species. On the other hand, some mycorrhizae increase metal tolerance by decreasing metal uptake in some low-accumulating species.
    Mycorrhizae thus assists Calluna in avoiding Cu and Zn toxicity. Most roots need about 100 times the amount of carbon than do the hyphae of its associated ectomycorrhizae in order to develop across the same amount of soil. It is therefore easier for hyphae to acquire elements that have a low mobility than it is for plant roots. Caesium-137 and strontium-90 both have low mobilities.
    Mycorrhizal fungi depend on host plants for carbon, while enabling host plants to absorb the soil's nutrients and water with more efficiency. In mycorrhizae, nutrient uptake is enhanced for the plants while they provide energy-rich organic compounds to the fungus. Although certain plant species that are normally symbiotic with mycorrhizal fungi can exist without the fungal association, the fungus greatly enhances the plant’s growth. Hosting mycorrhizae is much more energy effective to the plant than producing plant roots.
    The Brassicaceae family reportedly forms few mycorrhizal associations. But Hopkins (1987) notes mycorrhizae associated with Streptanthus glandulosus Hook. Some fungi tolerate easily the generally elevated metal contents of serpentine soils. Some of these fungal species are mycorrhizal. High levels of phosphate in the soil inhibit mycorrhizal growth.
    The uptake of radionuclides by fungi depends on its nutritional mechanism (mycorrhizal or saprophytic). Pleurotus eryngii absorbs Cs best over Sr and Co, while Hebeloma cylindrosporum favours Co. But increasing the amount of K increases the uptake of Sr (chemical analogue to Ca) but not that of Cs (chemical analogue to K). Moreover, the uptake of Cs decreases with Pleurotus eryngii (mycorrhizal) and Hebeloma cylindrosporum (saprophytic) if the Cs content is increased, but that of Sr increases if its content is increased – this would indicate that the uptake is independent from the nutritional mechanism.
    2 - Pollen and seed dispersal
    Some animals obtain food from the plant (nectar, pollen, or fruit pulp - Howe & Westley 1988). Animals feeding from hyperaccumulors high in metal content must either be metal-tolerant or dilute it with a mixed diet. Alternatively hyperaccumulators may rely on abiotic vectors or non-mutualistic animal vectors for pollen or seed transport, but we lack information on seed and pollen dispersal mechanisms for hyperaccumulating plants.
    Jaffré & Schmid 1974; Jaffré et al. 1976; Reeves et al. 1981; have studied metal contents of entire flowers and/or fruits. They have recorded elevated metal levels in these. There is an exception with Walsura monophylla Elm. (Meliaceae), originating from the Philippines and showing 7000 mg/kg Ni in leaves but only 54 mg/kg in fruits. Some plants may thus have a mechanism by which metal or other contaminants is excluded from their reproductive structures.
    d.    Commensalism
    This is an interaction benefiting one organism while being of neutral value to another. The most likely one with hyperaccumulators would be epiphytism. But this is most noticeable in humid habitats, whereas only a few detailed field studies of hyperaccumulators have been conducted in such habitats, and those studies (mostly to do with humid tropical forests on serpentine soils) pay little or no attention to that point (e.g., Proctor et al. 1989; Baker et al. 1992).
    Proctor et al. (1988) studied the tree Shorea tenuiramulosa, which can accumulate up to 1000 mg Ni/kg dry weight in leaf material.
    They estimated covers of epiphytes on the boles of trees in Malaysia, but did not report values for individual species. Boyd et al. (1999) studied the occurrence of epiphytes on leaves of the Ni hyperaccumulating tropical shrub Psychotria douarrei (Beauvis.).
    Epiphyte load increased significantly with increasing leaf age, up to 62% for the oldest leaves. An epiphyte sample of leafy liverworts removed from P. douarrei, was found to contain 400 mg Ni /kg dry weight (far less than the host plant, whose oldest and most heavily epiphytized leaves contained a mean value of 32,000 mg Ni/kg dry weight). High doses of Ni therefore do not prevent colonization of Psychotria douarrei by epiphytes.
    Chemicals that mediate host-epiphyte interactions are most likely to be located in the outermost tissues of the host (Gustafsson & Eriksson 1995). Also, most of the metal accumulates in epidermal or subepidermal cell walls or vacuoles (Ernst & Weinert 1972; Vazquez et al. 1994; Mesjasz- Rzybylowicz et al. 1996; Gabrielli et al. 1997).
    These findings suggest that epiphytes would experience higher metal levels when growing on hyperaccumulator leaves. But Severne (1974) measured the release of metal via leaching of leaves from the Ni hyperaccumulator Hybanthus floribundus (Lindl.) F. Muell. (Violaceae) from western Australia; he concluded that its leaves do not easily leach Ni.
    In theory another commensal interaction could exist, if the high metal content of the soil under hyperaccumulator plants was needed for another plant species to establish itself. No evidence is known showing such effect.
    The biofilm
    A biofilm is a layer of organic matter and microorganism formed by the attachment and proliferation of bacteria on the surface of the object. Biofilms are characterised by the presence of bacterial extracellular polymers glyocalyx that create a thin visible slimy layer on solid surface.
    The role of genetics
    Breeding programs and genetic engineering are powerful methods for enhancing natural phytoremediation capabilities, or for introducing new capabilities into plants.
    Genes for phytoremediation may originate from a micro-organism or may be transferred from one plant to another variety better adapted to the environmental conditions at the cleanup site.
    For example, genes encoding a nitroreductase from a bacterium were inserted into tobacco and showed faster removal of TNT and enhanced resistance to the toxic effects of TNT.
    Regulatory issues
    As of now phytoremediation is too new to be approved by regulatory agencies such as the EPA (USA).
    Eventually the main question that regulators will focus on is: will phytoremediation remediate the site to the standards and reduce the risk to human health and the environment?
    In developing regulations for phytoremediation the following questions will need answering.
    Can it cleanup the site below action levels? On what scale?
    Does it create any toxic intermediate or products?
    Is it cost effective as alternative methods?
    Does the public accept the technology?
    References
    Phytoremediation: Transformation and Control of Contaminants, edited by Steven C. McCutcheon and Jerald L. Schnoor
    The significance of metal hyperaccumulation for biotic interactions, by R.S. Boyd and S.N. Martens
    EPA citizens guide to phytoremediation - http://clu-in.org/PRODUCTS/CITGUIDE/Phyto.htm
    HSRC's phytoremediation page -http://www.engg.ksu.edu/HSRC/phytorem/
    Edenspace - http://www.edenspace.com
    Phytokinetics - http://www.phytokinetics.com
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