[PCOL and TOXICOLOGY] PPT environmental pollutants (Part 4 of intro)

Polychlorinated and Polybrominated Biphenyls (PBCs)

Used as

• Dielectric and heat transfer fluids, lubricating oils, plasticizers, wax extenders and flame retardants

Large industrial-site contamination, illegal dumping, migration from hazardous waste sites and widespread use of ____ in electrical transformers led to multiple localized areas of contamination and human exposure

Food

the major source of PCB in humans

Fishes

PCB can accumulate in what species

Dermatologic problems

Effects of PCB to workers

Polychlorinated and Polybrominated Biphenyls

Adverse effects:

Chloracne, folliculitis, erythema, dryness, rash, hyperkeratosis and hyperpigmentation

Hepatic abnormalities and elevation of plasma triglycerides

Polychlorinated and Polybrominated Biphenyls

Epidemiologic studies established increases in various cancers

Melanoma, breast, pancreatic and thyroid cancers

Perfluorinated compounds

• Used as coolant and air-conditioning, heat-, stain- and stick-resistant coatings for cookware

• Most common example is Teflon

Perfluorinated compounds

Teflon is what compound

Perfluorinated compounds

Present in nonstick pans

Perfluorinated compounds

• Centered on their estrogenic properties, accumulation and persistence in human

• Exposure takes place through ingestion and inhalation

• Enters food chain and water products – major source of human accumulation

3 years

Half life of

Perfluorinated compounds in humans

Perfluorinated compounds

Affects:

• Reproductive function, cellular proliferation, and other cellular homeostatic mechanisms

• Found to act on breast, kidney, prostate, ovarian cancers and non-Hodgkin lymphoma

Perfluorinated compounds

Symptoms include:

• Malaise, chills and fever, respiratory distress - Fume fever (acute pulmonary disorder)

• Noncardiogenic edema

Asbestos

• Have been widely used in industry

• All forms are shown to cause progressive fibrotic lung disease, lung cancer and mesothelioma

Chrysolite asbestos

Can cause an increase in lung cancer and mesothelioma

Metals

Occupational exposure and poisoning:

Beryllium, Cadmium

nonmetals (Manganese and Uranium)

On 206, Cobalt and cobalt-releasing compounds were listed as reasonably anticipated to be human carcinogens

Arsenic, Lead and Mercury

Metal poisons (3)

Beryllium

Light alkaline metal that confers special properties on alloys and ceramics

Used in computers, encasement of the first stage of nuclear weapons in devices that require hardening (missile ceramic cones), heat shield tiles and space vehicles

Beryllium

Highly toxic by inhalation and classified by IRAC as Class I, a known human carcinogen

Beryllium

Inhalation produces both acute and chronic disease – progressive pulmonary fibrosis

Progressive disease and may lead to sever disability, cancer and death

Cadmium

Transition metal used in nickel-cadmium batteries, pigments and low- melting point eutectic materials

Toxic by inhalation and ingestion

Cadmium

Common in welders

Shaking chills, cough, fever and malaise

Cadmium

Chronic exposure to _____ dust produces a far more serious progressive fibrosis and could also cause kidney cancer and renal failure

Class I

Cadmium is a human carcinogen class ___

Nonmetals

• any material, natural or manufactured

• Currently produced nanomaterials include gold, silver, cadmium

• Increase use of nanomaterials led to release of nanoscale substances into the workplace and general environment

Nonmetals

• Inhalational, oral ingestion, dermal absorption and parenteral administration of nanomaterial have been the source of human exposure

• Cytotoxic in lung cells

• Multiwalled carbon nanotubes cytotoxic in humans

Nanomaterials of nonmetals

can cross cellular membranes, may penetrate nuclear material and genetic information that may impact cellular response

Silica Nanoparticles

nonmetals demonstrates kidney toxicity in humans

Titanium dioxide

used in cosmetics are toxic to lungs and other organs