phlt 304 Toxicology in PH & Env Health

pptx

env health risk factors

• air pollution (inside & outside)

• water sanitation & hygiene

• chemicals & biological agents

• radiation (UV & ionizing & tanning beds)

• community noise

• occupational risks

• agricultural practices (pesticide use, wastewater reuse)

• built env (housing & roads)

indoor sources of contaminants

• modern building & furnishing materials

• animal hair & dander

• cleaning products

• cooking food → CO & gases

• paints & solvents → chemical fumes

• outdoor air pollutants

• mold & bacteria

• cigarette smoke

• fireplaces & woodburning stoves → combustion gases

• attached garage → CO & fumes

• gases seeping thru foundation

how do contaminants travel in the env

depends on chemical properties

exposure routes

• inhalation (respiratory)

• ingestion (gastrointestinal)

• dermal (skin)

respiratory tract absorption

lungs = large surface area → rapid uptake & release of molecules

small particles → move thru alveolar cells → organs while carrying absorbed materials

lithium ion battery fires

→ HF (toxic)

regular smoke < lithium smoke (uncontrollable, self-heating)

skin absorption factors

• damaged skin (cuts, abrasions)

• outer layer thickness (stratum corneum)

• skin temp (↑)

• chemical’s physical/chemical properties

• chemical concentration on skin

• time on skin

hair follicles, sweat ducts, sebaceous glands

gi tract absorption

ingestion: small intestine = large surface area → nutrient absorption

FDA w/dietary supp

X: review products for safety & effectiveness before marketed

✓: takes action against adulterated/misbranded products after marketed

ingestion exposure

• lack of manufacturing oversight

• natural X= good (natural plant/animal can be toxic)

• dose

chemical toxicity studies

• human epi studies

• animal studies (BUT can have diff ex. rats vs mice)

env risk assessment

• concentration in air/soil/water/food

• amt can get into person’s blood & tissues

• exposure route

• effect on health

• likelihood (@ env concentration) to cause harm to ppl