The incidence of low birth weight among white live-born infants from 1940 through 1978 was studied in various sections of the Love Canal. A statistically significant excess was found in the historic swale area from 1940 through 1953, the period when various chemicals were dumped in this disposal site. Potential confounding factors such as medical-therapeutic histories, smoking, education, maternal age, birth order, length of gestation, and urban-rural difference did not appear to account for this observation. Low birth weight rates were comparable to those of upstate New York from 1954 through 1978, the period when there was no deposition of chemical wastes.