Transgenic cotton and farmers’ health in Pakistan

Autoři: Shahzad Kouser aff001;  David J. Spielman aff002;  Matin Qaim aff003
Působiště autorů: Department of Economics, COMSATS University Islamabad, Islamabad, Pakistan aff001;  Environment and Production Technology Division, International Food Policy Research Institute, Washington, DC, United States of America aff002;  Department of Agricultural Economics and Rural Development, University of Goettingen, Germany aff003
Vyšlo v časopise: PLoS ONE 14(10)
Kategorie: Research Article
doi: 10.1371/journal.pone.0222617


Despite substantial research on the economic effects of transgenic insect-resistant Bacillus thuringiensis (Bt) cotton, there is still limited work on this technology’s impacts on human health. Due to the inbuilt insect resistance, Bt cotton requires fewer pesticide sprays than conventional cotton, which is not only advantageous from economic and environmental perspectives, but may also result in health benefits for farmers. Using socioeconomic and biophysical data from Pakistan, we provide the first evidence of a direct association between Bt gene expression in the plant and health benefits. A key feature of this study is that Bt cotton cultivation in Pakistan occurs in a poorly regulated market: farmers are often mistaken in their beliefs about whether they have planted Bt cotton or conventional cotton, which may affect their pesticide-use strategies and thus their pesticide exposure. We employ a cost-of-illness approach and variations in the measurement of Bt adoption to estimate the relationship between Bt cotton and farmers’ health. Bt adoption based on farmers’ beliefs does not reduce the pesticide-induced cost of illness. However, adoption based on measuring Bt gene expression is associated with significant health cost savings. Extrapolating the estimates for true Bt seeds to Pakistan’s entire Bt cotton area results in annual health cost savings of around US$ 7 million. These findings have important implications for the regulation of seed markets in Pakistan and beyond: improved regulations that ensure claimed crop traits are really expressed can increase the benefits for farmers and society at large.

Klíčová slova:

Agricultural workers – Cotton – Crops – Fiber crops – Gene expression – Health economics – Toxins – Pesticides


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2019 Číslo 10