Sunday, October 12, 2008

Fact #4

Fact #4: Cancer rates are up, particularly for cancers that affect the young

Cancer incidence increased steadily between 1973 and 1996, and probably for longer than that, although the government did not keep track of cancer rates before 1973. The increase was consistent across many types of cancer, from breast cancer, that increased steadily at 1.5 percent per year, to prostate cancer, that skyrocketed at 4.4 percent per year. Overall, cancer incidence in the U.S. rose by 1.1 percent per year during that time, or about 11,000 more cancers per million people each year. For some cancers the increase appears to have leveled off, but for many other cancers, rates continue to rise (NCI 1996, NCI 1997).

Isn't this just because people are living longer?

No. All of the rates represent the increase after accounting for an aging population.

Isn't the increase just the result of better detection?

For some portion of some cancers better detection explains the increase, but better detection does not account for the overall dramatic increases in cancer incidence that have occurred in the past 30 years (Ekbom 1998, NCI 1996, NCI 1997).

Childhood cancers on the rise

In the 20 years from 1975 to 1995, childhood cancer rates rose 20 percent, from 128 cases per million children in 1975 to 154 cases per million in 1995. Between 1992 and 1996, 20 of every 100,000 preschool-age children (four and younger) were diagnosed with cancer, or 200 times the one in a million lifetime risk level at which the federal government attempts to set regulations controlling chemical exposures. (NCI 1996)

Childhood leukemia: Leukemia, the most common childhood cancer, increased by about 17% between 1973 and 1996 (from 23 to 27 cases per million children) (EPA 2000).

Childhood brain cancer: The incidence of brain and other central nervous system tumors in children rose by 26% between 1973 and 1996 (EPA 2000).

Reproductive cancers on the rise

Since the chemical industrial revolution of the 1940's and 50's the population has been deluged with chemicals that disrupt normal functioning of the endocrine (hormone) system. Today, the average person born in the United States has 50 or more industrial chemicals in his or her blood that have been shown to disrupt normal functioning of hormones in animal studies. The levels of some of these compounds are similar to the amounts linked to adverse effects in animal studies. Many of these substances have also been shown to cause cancer of the testes, breast, prostate, and other reproductive organs in laboratory animals (Toppari et al 1996, Moline et al 2000, Schettler et al 2000). These chemicals include DDT, PCBs, dioxin, bisphenol-A, and phthalates, to name just a few. It is widely suspected that these compounds are contributing to increases in cancers of the reproductive organs in the human population.

Breast cancer. Among girls born today, 1 in 8 are expected to get breast cancer and 1 in 30 are expected to die from it. Invasive female breast cancer increased an average of 1.5 percent per year between 1973 and 1996, for a total increase of 25.3 percent. Among those 65 and younger, breast cancer incidence rose 1.2 percent per year, corresponding to a doubling every 2 generations (58 years). If trends continue, the granddaughters of today's young women could face a 1 in 4 chance of developing breast cancer. (NCI 1996, NCI 1997)

Testicular cancer. At its current pace, the incidence of testicular cancer is doubling about every one and a half generations (39 years). In the U.S. the incidence of testicular cancer rose 41.5 percent between 1973 and 1996, an average of 1.8 percent per year (NCI 1996, NCI 1997). While rates of testicular cancer continue to drop among older men (65 and up), younger men are not so lucky. Testicular cancer is the most common cancer among young men, disproportionately striking men in their 30's, with the highest rate of diagnosis among those between the ages of 30 and 34.

Prostate cancer. Prostate cancer rates rose 4.4 percent a year between 1973 and 1992, or more than a doubling of risk in a generation. Since 1992, the incidence has declined, but it is still 2.5 times the rate in 1973. Part of this increase can be explained by better detection, but increased incidence has also been accompanied by an increase in mortality - which better detection cannot explain. Prostate cancer is now the most common cancer among U.S. men, and the second most lethal, killing an estimated 31,900 men in the year 2000 alone (NCI 1996, NCI 1997).


Environmental Protection Agency (EPA). 2000. America's Children and the Environment. A first view of available measures. EPA 240-R-00-006. December 2000.
Moline JM, Golden A, Bar-Chama N, Smith E, Rauch M, Chapin R, Perreault S, Schrader S, Suk W, Landrigan P. September 2000. Exposure to hazardous substances and male reproductive health: a research framework. Environmental Health Perspectives. 108(9).
National Cancer Institute (NCI). 1996. SEER Cancer Statistics Review. 1973-1996.
National Cancer Institute (NCI). 1996. SEER Cancer Statistics Review. 1973-1996.
Schettler T, J Stein, F Reich, M Valenti. 2000. In Harm's Way: Toxic Threats to Child Development. Greater Boston Physicians for Social Responsibility. May 2000.
Toppari J, Larsen JC, Christiansen P, Giwercman A, Grandjean P, Guillette LJ Jr, Jegou B, Jensen TK, Jouannet P, Keiding N, Leffers H, McLachlan JA, Meyer O, Muller J, Meyts, ER-D, Scheike T, Sharpe R, Sumpter J, Skakkebaek NE. August 1996. Male reproductive health and environmental xenoestrogens. Environmental Health Perspectives. 104. Supplement 4.

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