Question

The plasticizer di-(2-ethylhexyl) phthalate (DEHP) is used widely in synthesizing plastics. Due to its heavy use and its ability to leak out of plastic products, it is important to analyze its potential to be toxic in humans.

c. Guinea pigs have very low levels of PPARa protein in their liver cells. They do not develop liver tumors upon exposure to DEHP. Is this difference due to a toxicokinetic or toxicodynamic effect? Explain.

d. Humans also have very low levels of PPARa in the liver. Imagine that you are charged with making recommendations on the safety guidelines for DEHP. What would you recommend? Why?

Answer 1

The plasticizer di-(2-ethylhexyl) phthalate (DEHP) is used widely in synthesizing plastics. Due to its heavy use and its ability to leak out of plastic products, it is important to analyze its potential to be toxic in humans.

c. Guinea pigs have very low levels of PPARa protein in their liver cells. They do not develop liver tumors upon exposure to DEHP. A number of studies on guinea pigs conductedon the effect of DEHP on markers of PPARa activation. In 2 weeks found that hepatic cyanide insensitive palmitoyl-CoA oxidation activity has not increased in guinea pigs as compared to rats and mice. also it shows no increase n liver weight and hepatic beta-oxidation activity in guinea pigs due to toxicodynamic effects.

d.Humans also have very low levels of PPARa in the liver. There are some saftey guidelines for DEHP which are explained as follows-

1. DEHP is used in the production of plastic products. plastic products that contain more than 1 per cent of DEHP are permanently banned from sale.

2.less exposure of medical devices and equipments which are made up of DEHP.

3. DEHP and other plasticizers are assessed for toxicity in number of other biolofical systems.

4. Ban the manufacturing of blood bags which are made up of DEHP.

5. No use of DEHP and other harmful plasticizers for processing and manufacturing the goods.

6. Concern over risk of exposure to DEHP plasticized plastics needs to be kept in proper perspective, in as much as many biomedical devices incorporating such as plastic provide therapeutic benefit often life saving.

7. As DEHP and other plasticizers causes tumors in liver, kidney swelling, problems in reproductive systems, lung cancer etc. proper and limited use of DEHP products has to be done.