1. Ministry of Agriculture
Translocation of Heavy Metals to Tomato ( Solanum lycopersicom L.) Fruit irrigated with Treated Wastewater
Omar B. Allahham
Ministry of Agriculture
Studies and Policies Department
Amman-Jordan
2010

2. Introduction
A field experiment was conducted to investigate the extent of translocation of heavy metals to tomato (Solanum lycopersicom L. cvs. ‘GS12 ‘ and ‘RS589956’ ) fruit produced in an open field near to Abu-Nusair Wastewater Treatment Plant , Amman-Jordan . Seedlings were planted during the seasons of 1999 and 2000 and furrow irrigated with different mixtures of potable water to treated wastewater { 100%:0% (1:0, control); 25%:75% (1:3); 50%:50% (1:1); 0%:100% (0:1)}. Tomato fruit , soil and water were examine for heavy metals concentrations, and changes in the pH and electrical conductivity (EC) of the soil were tested .
Treated wastewater can be used for irrigation under controlled conditions that minimize health risks from pathogenic and toxic pollution to the agricultural products , soil , surface and ground water.

3. Introduction
Treated wastewater is a good source of water to control problems such as wastewater disposition, lack of water availability in arid zones , in addition , it can improve soil quality for crop production.
Wastewater and sewage effluents contain significant quantities of heavy metals and other substances that may be toxic to people but beneficial to horticultural crops . Metals such as Zn, Cd, Pb, Fe, Cu, Mn, and Mo may be phytotoxic and /or if accumulated in the fruit will impose a health risk to humans.

4. Material and Methods Field experiment
Tomato seedlings of two cultivars , ‘GS12 ‘ and ‘RS589956’ , were transplanted , with no fertilizers added, in an open field near Abu-Nusair Wastewater Treatment Plant , Amman-Jordan.
Four treatments were applied in a three replicates , randomized complete block design (RCBD) with split plot arrangements
Experimental treatments were two cultivars grown with four mixtures , applied by furrow irrigation , of potable water to treated wastewater ratios at the following proportions: 100%:0% (1:0, control); 25%:75% (1:3); 50%:50% (1:1); 0%:100% (0:1) .

5. Sample collection and preparation
Material and Methods
Sample collection and preparation
Tomato fruit samples were hand harvested at an advanced full red stage of maturity (vine-ripe) by the end of July till the end of September at weekly intervals between harvests.
960 fruits were tested in this experiment.
Soil samples ( four samples from each depth ) were taken randomly at three depths ( 0-20, and cm) in each block, Samples were tested for their pH, Electrical Conductivity EC, and Heavy Metals
Water samples were collected in polypropylene bottles .

6. The pH of the soil and water was determined using a pH meter.
Material and Methods
3. Measurements
The Heavy Metals [ Cadmium (Cd), Copper (Cu), Iron (Fe), Manganese (Mn), Nickel (Ni), Lead (Pb) and Zinc (Zn) ] in the Soil, Water and in Fruit were determined by Graphite Furnace Atomic Absorption Spectrophotometry.
The electrical conductivity EC of the soil was determined directly by using a Conductivity Meter
The pH of the soil and water was determined using a pH meter.

7. Results and Discussion
Table1:Values of the soil pH, electrical conductivity (µs cm) and heavy metals concentrations (mg/kg) at three depths (0-20, and cm) in the soil measured prior to planting and after the last harvest following irrigation with treated wastewater.
Testa
Prior to planting
After harvest
Sig
LSD
0-20
0-40
40-60 pH
7.46
7.18
7.32
7.60
8.20 *
0.2182 EC
1418
1604
1431
1710
1064
1676
57.57 Cd
0.003
0.015
0.000
0.018
0.002 Cu
0.595
0.979
0.670
0.82
1.440
0.725
0.090 Fe
3.731
5.076
5.426
3.903
5.393
5.942
0.437 Mn
3.801
3.665
4.398
3.920
3.904
4.431
0.171 Zn
8.112
10.370
11.270
8.920
10.770
11.650
0.744 Ni
0.280
0.350
0.270
0.287
0.231
0.297
0.024 Pb
0.034
0.051
0.041
0.030
0.173
a Means are the average of 12 samples.
* Significant at P ≤

8. Heavy Metals a Cd Cu Fe Mn Zn Ni Pb
Results and Discussion
Table 2 : Heavy metal concentrations in four treatments (control 1:0; 1:1; 1:3 and 0:1 potable water to treated wastewater)
Treatment
Heavy Metals a Cd Cu Fe Mn Zn Ni Pb
1:0 (control)
0.000
0.330
4.130
0.180
2.460
0.300
1:1
0.670
11.980
0.160
3.970
0.550
1:3
0.970
12.220
0.260
10.150
0.760
0:1
1.360
0.370
11.790
0.210
Significance ns *
LSD -
0.199
2.778
2.828
0.509
a Means are the average of six samples.
*Significant at P ≤

9. Heavy Metals a Month Cd Cu Fe Mn Zn Ni Pb Results and Discussion
Table 3 : Heavy Metal concentration in the treated wastewater for3 months.
Month
Heavy Metals a Cd Cu Fe Mn Zn Ni Pb
July
0.000
1.137
11.700
0.240
7.230
0.680
August
0.440
8.190
0.270
5.420
0.100
September
0.910
10.530
0.220
8.620
1.340
Significance ns *
LSD -
0.730
2.406
2.449
0.441
a Means are the average of six samples.
*Significant at P ≤

10. Heavy Metals a Treatment Cd Cu Fe Mn Zn Ni Pb Results and Discussion
Table 4: Heavy metal accumulation in the fruit following four irrigation treatments (control 1:0; 1:1; 1:3 and 0:1 potable water to treated wastewater ).
Treatment
Heavy Metals a Cd Cu Fe Mn Zn Ni Pb
GS12
1:0 (control)
0.000
1:1
1:3
0.013
0:1
0.025
RS589956
0.007
0.100
0.050
0.020
0.075
0.035
0.300
a Means are the average of 60 fruits.

11. Results and Discussion
These results indicate that,
The accumulation of heavy metals varied according to cultivar, but was more pronounced with increasing the proportions treated wastewater used in irrigation of plants (the pattern of accumulation follows the order of 1:0 < 1:1 < 1:3 < 0:1).
In the two cultivars irrigated with potable water (control), no accumulation of heavy metals in the fruit was noticed.
The two tomato cultivars and the different fruit parts actually differ in their ability to accumulate heavy metals.

12. Conclusions
Irrigation with treated effluent increased the concentration of Cu, Fe and Mn accumulation at different soil depths, with an increase in the soil pH and salinity.
The increased levels of Cu, Fe and Mn in the soil was analogous to the increased concentration of these metals in the treated wastewater, indicating repositioning into soil, and then a strong possibility of, at least, partial translocation into the fruit.
The accumulation of heavy metals in tomato irrigated with treated wastewater was affected according to cultivar, plant part and the use of treated wastewater.

13. Conclusions
Tomato fruit from the ‘GS12’ cultivar accumulated Mn and Zn, whereas, fruit from ‘RS589956’ cultivar accumulated Fe, Cu, Mn, Ni and Zn.
Partial translocation of heavy metals from the soil to the fruit occurred, due to the presence of these metals in treated effluent, however, the concentration of these heavy metals in the fruit were below the standard limits.
The use of wastewater in irrigation of tomato fruit might be feasible because of it’s high nutritive value that may improve plant growth, reduce fertilizer application rates and increase productivity of poor soils.

14. Thank you
شكرا لحسن استماعكم
Ich Danke Ihre aufmerksamkeit