| PCBs and Liver Damage
Back
to PCBs and Liver Damage Table of Contents
Summary of PCB Studies Involving
(Each entry represents one finding in the sampling of 25 studies listed below. Some studies had multiple findings.) |
 |
- PCBs induce microsomal liver enzymes
- such induction may lead to hepatogenic porphyria and increased degradation of endogenous steroids in the liver
- PCBs are considered prototypes of workplace chemicals causing liver toxicity
- liver sensitivity should warn physicians that other organs may also be affected
- PCBs cause hepatomegaly (enlarged liver), liver hemorrhage, porphyria and liver damage
- the liver is the major target organ for PCBs
- PCBs produce porphyria
- the liver is the primary target of PCB carcinogenicity
- occupational PCB exposure is associated with subclinical alterations in serum enzymes suggestive of liver enzyme induction and possible hepatocellular damage
- PCBs have been responsible for porphyria outbreaks in Turkey and Japan
- PCBs stimulate drug metabolism and heme synthesis within 1 week of treatment
- PCBs cause hepatic porphyria, weight loss, tremor, liver damage and increased mortality
- PCBs cause increased accumulation of porphyrins, which causes hepatic porphyria in different species
- PCBs cause chronic hepatic porphyria
- qualitative changes in urinary porphyrins such as increases in uroporphyrin and heptacarboxylic-porphyrin, have been noted in PCB exposed workers
- urinary excretion of porphyrins can be one indicator of PCB exposure
- PCB caused porphyria, characterized by delayed development,
- PCBs caused increased excretion of urinary uroporphyrins and accumulation of carboxyporphyrins in the liver
- PCBs increased drug-metabolizing capacity of the liver.
- PCBs caused increased liver weight and porphyria
- PCBs increased all drug metabolizing pathways tested liver enlargement is observed that may progress to liver damage
- neoplastic liver nodules and hepatocellular carcinomas (liver cancer)
- porphyria, immunosuppression, and interference with steroid metabolism, which may be due to increases in microsomal enzyme activity associated with liver enlargement
- porphyrinogenic PCBs may increase ALA-synthetase by inhibiting UROD and therefore depleting heme
- hepatic porphyria due to PCBs is the best understood of the biological effects of this class of compounds
- PCBs cause enzyme induction and inhibition, changes in liver morphology, hepatic porphyria, and production of liver tumors
- PCBs cause hepatic porphyria
- biotransformation in the liver via hydroxylation and conjugation with glucuronic-acid, and varying degrees of metabolism and excretion according to specific molecular structures.
- abnormal findings on liver function tests have been found
- stimulation of enzyme production and porphyria
- PCBs were potent inducers of hepatic porphyria
- Furans had only a slight effect, if any
- hypobilirubinemia in PCB poisoning seems to be caused through either inhibition of heme catabolism or augmentation of bilirubin elimination
- PCB induces hepatic microsomal enzymes
- PCB induced hypobilirubinemia seems due mainly to accelerated bilirubin disposal from the blood
- liver enlargement, liver necrosis, and porphyria are some of the health effects noted in PCB poisoned birds in Green Bay
- liver morphological changes due to PCBs have been studied extensively.
- a widely studied effect is induction of hepatic microsomal enzymes in mammals
- PCBs are associated with porphyria
- porphyrins were slightly elevated in children born to PCB-exposed mothers
- PCBs may damage the cell membrane phospholipid structure causing the symptoms of porphyria cutanea tarda
- iron greatly sensitizes mice to PCB induced hepatic porphyria and liver tumor formation
- dietary selenium deprivation may render the livers of rats more sensitive to PCB effects
- PCBs induce liver enzymes (cytochrome P-450), which increases the oxidative stress caused by iron, which leads to porphyria.
- PCB-induced uroporphyria may be linked to liver tumors
- PCBs and iron together increase the incidence of porphyria and liver cancer
- PCB-induced cytochrome P450 (particularly the 1A2 isozyme) plays a key role in uroporphyria
- ascorbic acid (Vitamin C) prevents uroporphyria
- PCB Studies Involving the Liver
- Vitamins and Minerals May Change Our Vulnerability
- Links to More Information
- References
|
|
|
|
|
Make a Donation |