Words similar to pcbs
Example sentences for: pcbs
How can you use “pcbs” in a sentence? Here are some example sentences to help you improve your vocabulary:
For much of the 20 thcentury the secondary sex ratio (male births/all births) has been declining in many countries [ 16 17 18 ] . It has been speculated that this declining sex ratio is a sentinel indicator of environmental contamination [ 17 ] , although others have argued that, on a population level, this is not the case [ 16 18 19 20 21 ] . There is evidence, however, that hormonal levels around the time of conception are associated with the sex ratio of offspring [ 22 ] , and there is compelling evidence that exposure to particular chemicals does lead to changes in the sex ratio of offspring [ 23 24 25 26 27 ] , as seen, for example, with exposure to dioxins following an explosion at an herbicide plant in Seveso, Italy [ 26 27 ] . Animal studies have suggested that exposure to PCBs may lower the sex ratio of offspring [ 28 29 30 ] . Studies among human populations exposed to PCBs in different settings, however, have suggested increases [ 31 ] , decreases [ 32 33 ] , or no change [ 34 35 ] in the sex ratio.
It is possible that some chemical, or combination of chemicals, other than PCBs in the fish could lead to the changes in sex ratio we found, although this may be less likely given the specificity of our results for serum PCB and not DDE.
Total organochlorine pesticides plus PCBs should be less than 50 ng/L (APHA, 1992).
On one hand, there is increasing and rather convincing observational and experimental data underscoring the beneficial effects of marine fish consumption on fetal growth and gestation [ 1 2 3 ] . On the other hand, consumption of environmentally contaminated fish has been associated with decrements in gestation and birth weight in some studies [ 4 5 6 ] . Animal evidence suggests that Rhesus monkeys, rats and mice exposed to polychlorinated biphenyls (PCBs) in utero have reductions in length of gestation and growth [ 7 8 9 ] . The results from accidental environmental exposures also report adverse effects on birth size and ectodermal manifestations among fetuses to various polyhalogenated hydrocarbons [ 10 11 ] . One occupational study has reported a negative relation between PCB exposure and infant birth weight, which no longer remained significant after adjusting for gestation and other variables related to birth weight [ 12 ] . Results from a birth cohort study in the Faroe Islands, a community with a high intake of marine fish, whale meat and blubber, supported a relation between marine fatty acids and diminished birth weight for gestation, but the effects were not attributed to the mercury or PCB exposure [ 13 ] .
This hazard reflects the persistent and lipophilic nature of PCBs and related compounds and their ability to bioaccumulate within the aquatic food chain.
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