The Most Common Method of Determining Whether a Chemical Causes

question 54

Multiple Choice

The most common method of determining whether a chemical causes cancer is to expose groups of laboratory animals, such as rats, to various large doses and count how many animals develop cancer at the different levels. All of the following are problems with this approach in terms of understanding the health risks to humans EXCEPT:

• A)This method is indirect and uncertain as human and rats are different organisms and may respond differently to exposure to the same chemical.
• B)For expediting the research process, in lab settings rats are exposed to massive doses of suspected carcinogens relative to body size whereas humans are usually exposed to much lower amounts.
• C)For ethical reasons, rats in lab settings are given very small doses of suspected carcinogens relative to body size whereas humans are usually exposed to much higher amounts
• D)Risk assessment assumes that we can extrapolate from studies in rats to determine the expected rates of cancer in humans but extrapolating from one species to another and from one dose level to another is uncertain and may overestimate or underestimate a toxicant's danger.

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Definitions:

Inflation

The pace at which prices for services and goods generally ascend, reducing the value of money.

P/E Ratios

The Price to Earnings ratio, a valuation metric used to compare the market value of a stock to its earnings per share, indicating how much investors are willing to pay per dollar of earnings.

Expected Growth Rates

Forecasts of how fast particular economic indicators, such as sales or earnings, will grow over a specified period.

PEG Ratio

PEG Ratio stands for Price/Earnings to Growth ratio, a stock's valuation metric that evaluates a stock's price-earnings ratio relative to its earnings growth rate, offering insight into its future potential compared to its current earnings.