Based on this background, we have conducted a study with the following objectives.

By analyzing PCDDs, PCDFs, PCBs, and organochlorine insecticides in human breast milk collected from dumping sites of municipal wastes and control sites in some Asian developing countries, we have attempted;

1) To elucidate the contamination status of human breast milk from these Asian developing countries,

2) To assess the risk of exposure on infants, and

3) To evaluate the effects of dioxins on the thyroid hormone and Vitamin A in lactating women.

Samples of Human breast milk used in this study were obtained from residents around dumping sites of municipal wastes in India, Cambodia, Vietnam and Philippines during 1999 to 2001, as shown here.

In India, Cambodia and Vietnam, samples were also obtained from control sites, which are located more than 5 km far from dumping sites.

Additionally, blood serum samples were obtained from some of the above individuals, in order to analyze thyroid hormone and Vitamin A levels.

Informed consent was obtained before the collection of breast milk and blood from donors.

As shown here, these POPs such as PCDD, PCDF, PCB, DDT, HCH, chlordane, and HCB, were analyzed in this study.

Organochlorines analyzed in this study

Concerning first objective of this study, I would like to talk about contamination status.

This figure shows the mean concentrations of dioxins and related compounds, such as PCDDs, PCDFs, non-ortho PCBs, mono-ortho PCBs and their TEQs in human breast milk from residents around dumping sites in India, Cambodia, Vietnam and Philippines.

Dioxins and related compounds were detected in all the samples of human breast milk analyzed.

Among these compounds, mono-ortho PCBs were detected at the highest concentrations followed by PCDDs, non-ortho PCBs, and PCDFs in all the countries.

Interestingly, concentrations of all the compounds and TEQs of dioxin in India were higher than those in Cambodia, Vietnam and Philippines.

Mean concentrations of dioxins and related compounds in human breast milk from dumping sites

These figures illustrates the mean and range concentrations of dioxins and related compounds in human breast milk collected from dumping sites and control sites in India, Cambodia and Vietnam.

The X-axis shows concentrations of dioxins and related compounds, and the Y-axis shows dumping site (D) and control site (C) in India, Cambodia and Vietnam.

In India, the mean concentrations of all the compounds and TEQs of dioxins in human breast milk from dumping sites were higher than those from control sites.

This result suggests that significant pollution sources of dioxins and related compounds are present in the dumping sites in India.

On the other hand, in Cambodia and Vietnam, concentrations of these compounds in human breast milk from dumping sites were comparable to those from control sites.

Comparison of dioxins and related compounds concentrations in human breast milk from dumping and control sites

In the case of PCBs and organochlorine insecticides such as DDTs, HCHs, chlordanes and HCB, these contaminants were also detected in all the samples of human breast milk analyzed.

In Cambodia, Vietnam and Philippines, DDTs (blue) were detected at the highest concentrations, followed by PCBs.

In particular, DDTs levels in Vietnamese human breast milk (blue) were extremely high when compared with other countries.

Concentrations of HCHs, chlordanes and HCB were much lower levels than those of DDTs and PCBs.

However, HCHs in Indian breast milk shown by red bar were apparently higher than those in other countries.

The high contamination by HCHs found in Indian breat milk and DDTs in Vietnam breast milk agreed with earlier reports noted in food stuff and various wildlife.

Continuous usage of HCH and DDT are suspected in these countries.

Mean concentrations of total PCBs and organochlorine insecticides in human breast milk from dumping sites

The mean and range concentrations of PCBs and organochlorine insecticides in human breast milk collected from dumping sites were compared with those from control sites.

In Cambodia and Vietnam, concentrations of these compounds in human breast milk from dumping sites were comparable to those from control sites.

However, in India, concentrations of PCBs and chlordanes in dumping site were significantly higher than control sites, suggesting that significant pollution sources of PCBs and chlordans are present in the dumping sites in India, and the residents around there have been exposed to these contaminants.

Probably, PCB-containing electrical equipments such as older transformers and capacitors dumped are plausible sources for PCBs contamination in dumping site in India. The application of chlordane to eradicate pests might have conducted in this dumping site.

Comparison of PCBs and insecticides concentrations in human breast milk from dumping and control sites

Additionally, the residents in dumping site in India might be affected by exposure to these contaminants through consuming the bovine milk.

As seen here, buffalos and cows are feeding on the garbage in dumping site.

And the garbage fed bovines in dumping site return to the dairy farm in the evening and milked like this, and that milk is consumed by residents around here and sold in the market.

Thus the exposure and accumulation of toxic organochlorines originating from dumping site is unavoidable for residents through bovine milk.

Actually, as seen in next slide.

By the analysis of bovine milk from India, we found apparently higher concentrations of dioxins, PCBs and chlordanes in dumping site samples than in control sites.

Considering these results, it may be concluded that the residents in dumping site are exposed to dioxins, PCBs and chlordane through bovine milk.

Similar situation might be expected in other dumping sites in developing countries, if the domestic animals are feeding on garbage and residents use these animals and their products as food.

Comparison of TEQs, PCBs and CHLs concentrations in buffalo milk from dumping and control sites