- Full (HTML) - Related EHP Articles - PubMed:Related Articles - PubMed:Citation - Cited in PMC - Purchase This Issue

Terttu Vartiainen,^1,2 Leena Kartovaara,³ and Jouko Tuomisto^4,5

¹National Public Health Institute, Department of Environmental Hygiene, Kuopio, Finland
²Department of Environmental Sciences, University of Kuopio, Kuopio, Finland
³Statistics Finland, Population Statistics, Helsinki, Finland
⁴National Public Health Institute, Department of Environmental Medicine, Kuopio, Finland
⁵Department of Public Health and Community Medicine, University of Kuopio, Kuopio, Finland

Abstract

It has been proposed that environmental chemicalization is responsible for the recent decline in male ratio, but these speculations are based on statistics going back only a few decades. The objective of this study was to evaluate whether Finnish long-term data are compatible with the hypothesis that the decrease in the ratio of male to female births in industrial countries is caused by environmental factors. We analyzed the sex ratio of births from the files of Statistics Finland and all live births in Finland from 1751 to 1997. Running averages of 9 years (1751-1904) or 5 years (1905-1997) were analyzed for sex ratios. Additionally, to identify potential explanations for the findings, births from 1990 to 1997 were correlated with various family parameters. We found an increase in the proportion of males from 1751 to 1920 ; this was followed by a decrease and interrupted by peaks in births of males during and after World War I and World War II. None of the family parameters (paternal age, maternal age, age difference of parents, birth order) could explain the time trends. The turning point of male proportion precedes the period of industrialization or the introduction of pesticides or hormonal drugs, rendering a causal association unlikely. Moreover the trends are similar to those observed in other countries with worse pollution and much greater pesticide use. Key words: chemicalization, dioxins, male proportion, pesticides, pollution, polychlorinated biphenyls, sex ratio. Environ Health Perspect 107:813-815 (1999) . [Online 1 September 1999]

http://ehpnet1.niehs.nih.gov/docs/1999/107p813-815vartiainen/ abstract.html

Address correspondence to T. Vartiainen, National Public Health Institute, Division of Environmental Health, P.O. Box 95, FIN-70701 Kuopio, Finland. Telephone: 358-17-201 346. Fax: 358-17-201265. E-mail: terttu.vartiainen@ktl.fi

We thank J. Pekkanen for useful discussions and E. MacDonald for checking the English language.

Received 9 March 1999 ; accepted 27 May 1999.