Relatively little is known about how environmental and pathological threats to human survival and longevity are perceived by the public. In this study in rural Bangladesh and West Bengal, India, which used individual interviews and focus-group discussions to investigate the changing costs of and motivations for reproduction, respondents were questioned about their perceptions of changes in mortality. The findings show that, while child mortality levels are perceived to have fallen dramatically in recent times, the health and survival prospects of the middle aged and the elderly are seen to have been better in the past. The perceived decline in adult health is attributed to environmental deterioration and lifestyle changes accompanying modernization. This paper explores people’s reasons for this unexpected worldview. References to pesticides and chemical fertilizers as causes of death abound in their explanations and are seen to be associated with unhealthy agricultural practices and impiety.