Evaluating environmental and social influences on iron and zinc status of pregnant subsistence farmers in two geographically contrasting regions of Southern Malawi

• Published in: The Science of the total environment 2014-12, Vol.500-501, p.199-210
• Main Authors: Dickinson, N., Rankin, J., Pollard, M., Maleta, K., Robertson, C., Hursthouse, A.
• Format: Article
• Language: English
• Subjects: Adult; Agriculture; Blood; Communities; Environmental Pollutants - metabolism; Female; Humans; Interdisciplinary; Iron; Iron - metabolism; Life Sciences; Maize; Malawi; Maternal Exposure - statistics & numerical data; Micronutrients; Micronutrients - metabolism; Pilot Projects; Pregnancy; Santé publique et épidémiologie; Socioeconomic Factors; Soil; Soil (material); Staples; Statistical analysis; Trace Elements - metabolism; Zea mays; Zinc; Zinc - metabolism
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2014.08.087

Micronutrient deficiency affects over 4.5 billion people worldwide, the majority in developing countries. Deficiencies of iron (and associated anaemia) and zinc in pregnancy are associated with complications, maternal and neonatal mortality, and developmental disorders in the foetus and growing child. We report the results of pilot study which used an interdisciplinary approach to explore environmental and sociocultural factors influencing the micronutrient status in the soil–plant–human transfer for pregnant subsistence farmers in two geographically contrasting regions of Southern Malawi. It evaluated micronutrient status in soil and the staple crop and explored the context for their transfer to pregnant women. Scientific and social science methods were used to collect data, following full sensitisation of the communities. A total of 99 participants were recruited from Chiradzulu (plateau) and Chikwawa (floodplain). Soil, maize and blood samples were collected, along with food frequency and health behaviour questionnaires and anthropological observation. Statistical analysis revealed that soil iron was significantly higher in Chiradzulu than in Chikwawa; total iron concentration is not deemed to be deficient in either area. Soil zinc was not significantly different between areas. Maize concentrations of iron and zinc were not significantly different between areas, and were not deficient relative to improved cultivars. Blood iron deficiency and associated anaemia were problematic in both areas, but more so in Chikwawa than in Chiradzulu, and zinc deficiency was similar in both areas. The study has identified a significant difference in the blood iron status of the participants of the two communities, and has shown that this difference is not accounted for by the staple crop maize. Socio-geographical factors appear to play a significant role in the micronutrient health of the populations. The findings lend support to multifaceted community intervention studies which educate communities on strategies to tackle micronutrient deficiencies. [Display omitted] •Soil iron higher in plateau than floodplain region. Soil zinc low in both areas.•Maize iron and zinc not deficient relative to improved cultivars.•Blood iron deficiency and anaemia prevalent in both areas. Zinc less problematic.•Diet, comorbidities and social landscape may explain differing anaemia prevalence.•Trends in nutrient status not accounted for by simple soil-plant-human transfer.