Exam 3 - Environmental Health

Define pesticide

substance used to kill, repel, or control plant or animal life considered a pest

What are compounds used for?

control mice and rats

What are disinfectants used for?

preventing the spread of bacteria

List some examples of pesticides

disinfectants, fumigants, fungicides, herbicides, insecticides, repellents, rodenticides

What are POPs?

chemicals of global concern

Why are POPs an issue? (4)

long-range transport, persistence in environment, biomagnification in the food chain, overall negative human/environmental impacts

Organophosphates pesticides pros

inexpensive, control wide range, do not persist in environment

Organophosphates pesticides issues

frequent cause of fatal poisonings

What are organophosphates pesticides used in?

sprays, baits, flea collars, pet shampoo, indoor foggers

How do organocarbamates (or carbmates) act in the environment?

dissipate quickly due to breaking down into other substances

Where are organocarbamates used?

controlling garden pests (wasps, hornets, snails) and flea/tick prevention in pets

What happened in the MIC release in Bhopal, India?

accidental release of MIC (organocarbamates) in industrial accident
acute exposure extremely toxic to all life

Where are pyrethoids derived from?

natural sources (chrysanthemum flowers)

Why are organochlorides harmful?

fat-soluble and stay in the environment, bioaccumulate in the food chain

What are negative health outcomes are organochlorides associated with?

supression of the immune system and cancer

The ‘golden age of discovery” of insecticides generally refers to what time period?

mid-1900s

When did DDT become widespread and used the most?

use begun: 1940s
max use: 1960s

What was DDT used to control?

mosquitos carrying malaria

What positive thing is DDT credited with?

saving millions from malaria

When was DDT use prohibited and why?

1972 because of concern for adverse effects of human health and wilflife

Who is responsible for approving pesticides for use in the US?

EPA

When was agent orange used?

Vietnam War

What are concerns of using pesticides (4)?

harm to agriculture workers, undesirable effects on cattle, drift into school/homes, unintentional killing of pets

How was Southern California positviely impacted by pesticide use?

cyanide extraction techniques saved citrus industry from pet-induced collapse, cheap way to keep pests away

Why is it difficult to determine the effects of endocrine disruptors?

people usually exposed to multiple

What are PFAS used for?

industrial applications and non-stick pans, paper, textile coatings

What are PCBs used for?

electrical equipment (transformers, heat transfer fluids, lubricants)

What are the health effects of PCBs?

cancer in animals, probable human cancer, possibly impact on immune/reproductive system and chilren’s cognitive function

What is atrazine used for?

herbicide on farms

What are the issues with atrazine?

washed from soil into streams and other bodies of water, long lasting in water

How did the government control atrazine use?

require license to purchase

What act makes the EPA responsible for regulating pesticides?

Fungicide and Rodenticide Act and Food Quality Protection Act

Summarize the video about Dr. Tyrone Hayes.

research on frogs that shows the potential harmful effects of atrazine use
argued for environmental justice and gov/large companies cover up

Non ionizing radiation

form of radiation on the left of the electromagnetic spectrum

ionizing radiation

energy that acts by removing electrons from atoms and molecules

Event that became symbol for antinuclear movement

Chernobyl

What in residential areas can cause negative health outcomes through non-ionizing radiation?

high tension power lines

Difference between harm in UVA and UVB radiation

UVA radiation is weaker but penetrates deeper into skin, more constant throughout the year

What is radioactive decay?

radioactive atom spontaneously gives off radiation to reach a more stable state

What is ionizing activity?

alter molecules within body cells that can eventually cause cancer

What is the easiest radioactive isotope to block?

alpha particles

Which radioactive isotope requires concrete/steel/lead to block?

gamma rays

If you ingested/inhaled a radioactive isotope, which would be the most harmful? the least?

Most: alpha

Least: gamma

What geologic formations naturally contain radioactive elements?

uranium and radon

Anthropogenic sources of ionizing radition

diagnostic radiation, nuclear power plants, industry, production/testing of nuclear weapons

Curie (Ci)

unit of measure to describe amount of radioactivity in a sample material

Rad

radiation absorbed dose

former unit of absorbed dose of ionizing radiation

Becquerel (Bq)

corresponds to radioactivity

Gray (Gy)

corresponds to absorbed dose

Exposure

describe amount of radiation traveling through the air

Adsorbed dose

amount of radiation absorbed by an object or person

effective dose

amount of radiation absorbed by person adjusted for type of radiation and organ

Factors effecting amount of radiation exposure

amount of time, distance from source, rate of energy emission

Stochastic

random

nonstochastic effects (acute)

tissue burn, radiation sicknes

What type of study was the Hiroshima & Nagasaki article?

retrospective/prospective cohort

What is the hydrological cycle?

natural cycle that water evaporates from bodies of water and accumulates as water vapor, returns to oceans, and other water bodies as precipitation

Why do freshwater lakes become salty?

evaporation (especially in arid areas)

Surface water examples

lakes, rivers, reservoirs, ponds

What is groundwater?

water contained in connected pores of aquifer

What is an aquifer?

section of Earth that contains freshwater(groundwater)

Water withdrawal

removal of freshwater for human use from any natural source/reservoir
if not consumed water may return to environment to be used again

Renewable water

freshwater coninuously replenished by hydrological cycle (water in rivers, lakes)

Nonrenewable water

water in aquifers that is not recharged by the hydrological cycle or slowly that human use causes depletion

What parts of the world have severe water shortages and experience high population growth rates (2)?

sub-Saharan/Northern Africa and the near east Asia

Define waterborne disease

conditions transmitted through ingestion of contaminated water, water acts as passive carrier of infectious agent

Define aeration

increase in dissolved oxygen that improves overall quality and reduces corrosiveness

What does coagulation do in drinking water treatment?

removes suspended material

What does sedimnetation do in drinking water treatment?

cause heavy particles to settle to bottom of tanks for collection

What does filtration do in drinking water treatment?

remove smaller particles

What does disinfection do in drinking water treatment?

destroys pathogens

What does the Surface Water Treatment Rule enforce?

water systems must filter and disinfect surface water sources to reduce illnesses caused by pathogens in drinking water

What does the Ground Water Rule aim to acheive?

approach to target ground water systems vulnerable to fecal contamination, systems at risk must take corrective action when water systems will use ground water as source of drinking water

What are the downsides of conventional wastewater treatment?

relatively expensive and energy intensive

What are the benefits of ecological wastewater treatment?

low energy input and costs

What is the downside of ecological wastewater treatments?

increase land space requirements and not suitable for all climates

What is the benefit of conventional wastewater treatment?

effective pathogen inactivation

Main concern for beach and coastal pollution

runoff sewage contamination in ocean can expose people to waterborne diseases