Environmental Engineering Reference
In-Depth Information
marine mammals from Arctic waters, suggesting widespread
global distribution. PFOS in nursing Hudson Bay beluga
whale calves exceeds the oral reference dose (the level con-
sidered safe for humans), which raises concern for harmful
effects in sensitive Arctic marine wildlife. One wonders why,
when there was so much concern and attention to chlorinated
chemicals (DDT, PCBs) decades ago, people didn't realize that
brominated and fluorinated chemicals would be likely to have
similar behavior in the environment and similar effects and
look into them.
What is the concern about alkylphenols?
Alkylphenols are chemicals used in the production of deter-
gents and other cleaning products, personal hair care prod-
ucts, and commonly used plastics. They are also known to be
endocrine disruptors, specifically estrogen mimics. One alkyl-
phenol, bisphenol-A (BPA), has been the subject of concern and
controversy regarding its potential adverse effects on human
health, particularly children's development, and until recently it
was commonly used in plastic baby bottles and other products.
In 2008 Canada banned the use of BPA in baby bottles. Most
scientists who study alkylphenols consider them serious envi-
ronmental hazards with hormone disruptive effects in humans
and wildlife, including marine animals. For example, scientists
have found extensive contamination in lobsters in urban areas,
and that alkylphenols are toxic to them at low doses, interfer-
ing with metamorphosis and shell hardening. Reproductive
and developmental effects of BPA in fishes include decrease of
male hormones, death of testicular cells, inhibition of sperm
and egg production, and decreased hatchability of larvae.
What are nanoparticles and what is the concern about them?
Nanotechnology is used in many areas of modern life, includ-
ing the manufacture of paints, batteries, fuel additives, catalysts,
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