Translocation of heavy metals in Jatropha curcas (Physic Nut) grown in abandoned mine area

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A report on the study conducted to look into the heavy metal (HM) uptake and translocation in Jatropha curcas. Specifically the study (1) assessed the adaptability of J. curcas in the abandoned mine area of Mogpog, Marinduque, (2) determined the translocation of heavy metals to various plant organs of Jatropha up to the fruiting stage, and (3) assessed the effects of some mitigating measures to regulate the transport of heavy metals using microbial amendment in the form of mycorrhiza.

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Nina M. CadizInstitute of Biological Sciences

University of the Philippines Los Baños

Translocation of Heavy Metals in Jatropha curcas (Physic Nut)

Grown in Abandoned Mine Area

UPLB BASIC RESEARCH- Fund Code: 88-D60-23

Study presented on March 30, 2010, OVCRE, UPLB

Once metals are introduced and contaminate the environment, they will remain.

In general it is very difficult to eliminate metals from the environment. Metals are not degraded easily.

However, concentration in the soil may be reduced.

Heavy metal pollutated areas need REHAB!

BACKGROUND…

Excess heavy metal accumulation in soils is toxic to humans and other animals.Exposure to heavy metals is normally chronic due to food chain transfer.Chronic problems associated with long-term heavy metal exposures are:

•Lead – mental lapses•Cadmium – affects kidney, liver, and GI tract•Arsenic – skin poisoning, affects kidneys and central nervous system.

Heavy metal pollutated areas need REHAB!

Need:

Management of Contaminated Soil by carefully selecting plants for use on metal-contaminated soils

Why Jatropha?

Hype on Jatropha as cheap source of biodiesel

Lead to exhaustive research and massive planting of Jatropha

http://www.jatropha.de/news/jcl-news.htm

Oasis in the desert: Jatropha cultivation can halt soil erosion, increase water storage in the soil and transform barren expanses into lush, productive land.

My inspiration:

Questions:

Can Jatropha be used as a phytoremediation species?

Can it grow well in abandoned mine areas, for instance?

Would it translocate the heavy metals (HMs) to the fruits?

If YES, this then would be an environmental concern since seeds are processed for biodiesel – magnify problem of HM pollution

The main objective of the study is to look into the heavy metal (HM) uptake and translocation in Jatropha curcas.

Specific Objectives

1. Assess the adaptability of J. curcas in the

abandoned mine area of Mogpog, Marinduque

2. Determine the translocation of heavy metals to

various plant organs of Jatropha up to the fruiting

stage

3. Assess the effects of some mitigating measures to

regulate the transport of heavy metals using microbial

amendment in the form of mycorrhiza.

THE STUDY AREA

Satellite image of the 32 hectares abandoned mine site

(Cu mining) in Mogpog, Marinduque(Source: http://maps.google.com.2009)

Experimental site in Brgy. Capayang, Mogpog, Marinduque

Experimental site in Brgy. Capayang, Mogpog, Marinduque

Part 1. Growth assessment of Jatrophaoutplanted in Mogpog, Marinduque

Treatment Height(cm)

Diameter(cm)

Uninoculated 3.88 b 0.231 c

MykoVAM 4.55 ab 0.554 bc

MineVAM 4.33 b 0.503 bc

Table 1. Growth of J. curcas treated mycorrhiza three months after transplanting in an abandoned mine site in Barangay Capayang, Mogpog, Marinduque.

0

5

10

15

20

25

30

Height (cm)

Control MykoVAM MineVAM

Treatments

Height of Jatropha outplanted in an abandoned mine site in Mogpog,

Marinduque 10 mos after establishment.

10.5

11

11.5

12

12.5

Diameter (cm)

Control MykoVAM MineVAM

Treatments

Diameter (cm) of Jatropha outplanted in abandoned mine site in Mogpog,

Marinduque 10 mos after establishment.

Height not improved as compared with the control.

Diameter not improved as compared with the control.

Part 2. Translocation of heavy metals in Jatropha curcasgrown in abandoned mine site in Mogpog, Marinduque

Treatments

Heavy

Metals A. Roots B. Stems C. Leaves

Uninoculated Copper 57.175 60.971 24.664

Zinc 26.119 8.636 4.925

Cadmium 0.000 0.000 0.161

Lead 13.346 17.077 28.161

+MykoVAM Copper 63.948 42.194 23.403

Zinc 17.343 6.655 13.689

Cadmium 0.000 0.000 0.000

Lead 17.661 8.539 9.498

+MineVAM Copper 56.756 34.535 42.867

Zinc 18.942 5.319 0.727

Cadmium 0.000 0.000 0.000

Lead 2.949 9.039 10.917

Table 1. Concentration (mg/kg) of copper, zinc, cadmium and lead (mg/kg) of Jatropha roots, stems and leaves grown in Mogpog, Marinduque. Values are averages of three replicates.

Plant Organ

Uninoculated (Control)

Inoculated(MykoVAM & Mine VAM)

Roots Zn Cu, Pb, Zn

Stems Cu

Leaves Pb, Cd (but very very

low concentration)

Pb (highest with

MineVAM)

Fruits None None

Metal Translocation(Plant organ with highest HM concentration)

In general, translocation of HMs to upper parts was regulated by mycorrhizal treatments.

Possible reason:

Mycorrhiza also absorbed the HMs thus reduced translocation to upper plant organs.

Metal translocation: (Inoculated)

Cadmium (Cd) uptake

Nil to zero

Possible reason:

Very low Cd concentration in the soil based on initial analysis.

Fruit Analysis

Analysis of fruits collected from vicinity of various abandoned mine areas in the Philippines (including Mogpog) showed negative HM concentration.

Reason: Plants translocate larger quantities of metals to their leaves than to their fruits or seeds.

Implication: Greater risk of food chain contamination since forage is eaten by livestock.

CONCLUSION:

Are HMs translocated in Jatropha fruits?

No.

Can Jatropha grow in abandoned mine or HM-polluted areas?

Yes, provided that soil amendments are placed.

Is Jatropha a good phytoremediation species?

No.

FUTURE PROSPECTS

Phytoremediation is an excellent green-technology to cleanup heavy metal contaminated areas.

Further research is needed to look for ways of regulating HM translocation to the aerial parts of the plants to assure that tissues of plants used for phytoremediation do not have adverse environmental effects if eaten by wildlife or used by humans (e.g. mulch or firewood)

Research is also needed to find more efficient bioaccumulators, hyperaccumulators that produce more biomass.

Acknowledgement

OVCRE-UPLB for funding the research

Collaborators in Mogpog, Marinduque

LGU – Mayor Libello

Capayang Elementary School

DENR, Marinduque

Thank you for listening....

Potentially contaminated soils may occur at: old landfill sites

old orchards that used insecticides containing arsenic as an active ingredient

fields that had past applications of waste water or municipal sludge

areas in or around mining waste piles and tailings

industrial areas where chemicals may have been dumped on the ground, or

in areas downwind from industrial sites

Phytoextraction Process of growing plants in metal

contaminated soil .

Plant roots translocate the metals into aboveground portions of the plant.

After plants have grown for some time, they are harvested and incinerated or composted to recycle the metals. Several crop growth cycles may be needed to decrease contaminant levels to allowable limits.

If the plants are incinerated, the ash must be disposed of in a hazardous waste landfill.

Volume of the ash is much smaller than the volume of contaminated soil if dug out and removed for treatment.

Sources of Heavy Metal in Soils

Mining, manufacturing, and the use of synthetic products (e.g. pesticides, paints, batteries, industrial waste, and land application of industrial or domestic sludge)

Heavy metals also occur naturally, but rarely at toxic levels.

The most common problem causing cationic metals (metallic elements whose forms in soil are positively charged cations e.g., Pb2+) are mercury, cadmium, lead, nickel, copper, zinc, chromium, and manganese.

The most common anionic compounds (elements whose forms in soil are combined with oxygen and are negatively charged e.g., MoO42-) are arsenic, molybdenum, selenium, and boron.

Phytoextraction Plant roots translocate the metals into

aboveground portions of the plant.

After plants have grown for some time –

harvested and incinerated or composted to recycle the metals.

If the plants are incinerated, the ash must be disposed of in a hazardous waste landfill.

Volume of the ash is much smaller than the volume of contaminated soil if dug out and removed for treatment.

Block Copper (mg/kg)

Cadmium (mg/kg)

Lead (mg/kg)

Zinc (mg/kg)

Block 1 84.95 ± 0.63 0.033 0.399 4.532 ±0.015

Block 2 71.60 ± 2.28 0.022 0.941 4.752 ±0.174

Block 3 56.36 ± 0.33 0.022 0.694 3.656 ±0.024

MEAN 70.97 ±1.08 0.026 0.678 4.313±0.071

Table 2. Initial heavy metal analyses of soil collected in Mogpog, Marinduque. (reported during the 1st year of operation).

Element Target value

(mg kg-1 soil)

Intervention

value*

(mg kg-1 soil)

Cadmium 0.8 12

Copper 36 190

Mercury 0.3 10

Lead 85 530

Zinc 140 720

Dutch standards for soil contamination

assessment, in terms of total concentration

of heavy metals in soils.

*Intervention value - This indicates serious contamination of soils where

remediation is necessary.

Treating metal contaminants

By phytoextraction, rhizofiltration

and/or phytostabilization