Chapter 17

How many deaths per year is Malaria responsible for?

1-2 million

Cigarettes kill how many people per day?

14,800 people

Tuberculosis is what percent of deaths in developing countries?

84%

What is the difference between transmissible and nontransmissible diseases?

A nontransmissible disease is not contagious and is not caused by a living organism invading the body. Transmissible diseases are contagious and are caused by pathogens, living organisms, invading the body.

Describe the threshold dos-response model.

After a certain dose, the chemical is harmful to the human body.

Describe the nonthreshold dose-response model.

Any dosage of a chemical is harmful to the human body.

Humans suffer from what five hazards?

Biological, Chemical, Physical, Cultural, and Lifestyle

Describe the controversy over the chemical Bisphenol A.

Bisphenol A is chemical used in a variety of products including water and baby bottles, sports drinks and juice bottles, microwave dishes, food storage containers , food and beverage can liners, and dental fillings. However 94 studies show that Bisphenol A can leak into the previously listed products and cause brain damage, prostate disease, breast cancer, early puberty, reduced sperm count, impaired immune function, type 2 diabetes, hyperactivity, and etc. However, 12 studies found no evidence or weak evidence from low-level exposure to this chemical. This controversy could take decades to solve.

What are carcinogens?

Carcinogens are chemicals, types of radiation, or viruses that cause or promote cancer

What are three major types of potentially toxic agents?

Carcinogens, mutagens, and teratogens

Describe the negative effects of hormonally active agents.

Exposure to them can impair reproductive systems and sexual development and cause physical and behavioral disorders.

What are the three most dangerous viruses?

FLU, Human deficiency virus (HIV), and Hepatitus B

What chemicals can mimic hormones?

Hormonally active agents

What are mutagens?

Includes chemicals or forms of radiation that cause mutations, or changes, in the DNA molecules found in cells, or that increase the frequency of such changes

What is risk management?

It involves deciding whether or how to reduce a particular risk to a certain level and at what cost.

What is toxicity?

It is a measure of how harmful a substance -- its ability to cause injury, illness, or death to a living organism.

Define lethal dose.

Lethal dose is the amount needed to kill an animal.

Describe Mercury's toxic effects briefly.

Mercury is a teratogen and a neurotoxin that interferes with the nervous system and brain function. It causes brain damage in fetuses and young children.

What are the two general types of dose-response curves?

Nonthreshold dose-response model and threshold dose-response model

What is a toxic chemical?

One that can cause temporary or permanent harm or death to humans and animals.

What are PCBs?

Polychlorinated Biphenyls, are a class of mroe than 200 chlorine- containing organic compounds that are very stable and nonflammable.

What is the difference between possibility and probability?

Possibility means an event can happen. Probability is the likelihood of that event occurring.

Define/Describe case reports.

Reports,usually made by physicians, that provide information about people suffering adverse health effects or death after exposure to a chemical.

Why are PCB's harmful?

Research showed that PCB's could cause liver and other cancers, and learning disabilities to children.

What does risk analysis involve

Risk analysis involves identifying hazards and evaluating their associated risks, ranking risks, determining options and making decisions about reducing or eliminating risks and informing decision makers and the public about risks.

Why is risk assessment useful?

Scientists use it to estimate the probability of a risk, to compare it with the probability of other risks, and to establish priorities for avoiding or managing risks.

What is dose?

The amount of a harmful chemical that a person has ingested, inhaled, or absorbed through the skin.

Are trace levels of toxic chemicals harmful?

The answer to this question is unknown.

What is biological magnification?

The concentration of some potential toxins in the environment increase they pass through the successive trophic levels of food chains and webs.

Define median lethal dose (LD50).

The dose that can kill fifty percent of the animals in a test population within an 18 -day period

What is a risk?

The probability of suffering harm from a hazard that can cause injury, disease, death, economic loss, or damage

What are x and y axis labeled on the dose-response curve?

The x axis is the dose in a certain unit and the y axis is the percentage of population killed by a given dose.

What are teratogens?

They are chemicals that cause harm or birth defects to a fetus or embryo.

When is a dose- response curve used?

To estimate the effects of various doses of the chemical on test organisms?

What is toxicology?

Toxicology is the study of the harmful effects of chemicals on humans and other organisms. It is the study of poisons.

What disease infects 9.2 million per year?

Tuberculosis

What are common diseases that humans contract from mosquitos

West nile and Malaria

Are nontransmissble diseases the main cause of death currently?

Yes

An immediate or rapid harmful reaction to an exposure is an...

acute effect

A permanent or long-lasting consequence is a...

chronic effect

Damage to health resulting from exposure to a chemical is called a ...

response