Exposure to environmental chemicals on the decline

AORN Journal, Dec, 2005

The Centers for Disease Control and Prevention (CDC) has released a report that shows a significant decline in exposure to secondhand smoke and continued decreases in cotinine and lead Levels in children's blood, according to a July 21, 2005, news release from the CDC. The Third National Report on Human Exposure to Environmental Chemicals also suggests the need for more research into health effects of exposure to low levels of cadmium.

Levels of the chemical cotinine, which is a marker of exposure to secondhand smoke in nonsmokers, first measured from 1988 to 1991, have dropped significantly. Compared to median levels for 1988 to 1991, median cotinine levels measured from 1999 to 2002 have decreased 68% in children, 69% in adolescents, and approximately 75% in adults. Non-Hispanic blacks have levels twice as high as those of non-Hispanic whites or Mexican Americans, however, and children's levels are twice as high as adults' levels.

Elevated blood lead levels (ie, levels of 10 mcg per deciliter or greater) in children ages one to five years also have declined; 4.4% of children measured in the early 1990s had elevated levels compared to 1.6% of children measured from 1999 to 2002. Although the decreased blood lead levels in children is an accomplishment, researchers say there is no safe blood Lead Level in children.

Recent studies have shown subtle kidney injury and Low bone mineral density may be associated with urine levels of the metal cadmium as low as 1 mcg per gram of creatinine. The report shows that approximately 5% of the US population ages 20 years and older had urinary cadmium at of near these elevated levels, which may be attributable to cigarette smoking.

CDC Releases Extensive Survey of Americans' Exposure to Environmental Chemicals (news release, Atlanta: The Centers for Disease Control and Prevention, July 21, 2005) http://www.cdc.gov/od/oc/media/pressrel/r0S0721.htm (accessed 3 Oct 2005).