are NOT a source of arsenic in the environment. * Pesticides
Rocks that naturally contain the element
Weed killers
Old water pipes

What policy change was based on the results of the students’ water-testing project? *
The U. S. Environmental Protection Agency established a national limit for arsenic in drinking water.
The national limit for arsenic in drinking water was lowered to 5 parts per billion (ppb).
The national limit for arsenic in drinking water was increased to 10 ppb.
New Hampshire’s limit for arsenic in drinking water was lowered from 10 ppb to 5 ppb.

Damage to the body’s system can affect brain development, learning, and memory. *
cardiovascular
muscular
endocrine
nervous
4. The element arsenic is a . *
metalloid
metal
nonmetal
noble gas
5. Explain how the characteristics of arsenic can make it difficult to know whether a well is contaminated. *