Abstract:
Background: Fish is recognised as a rich source of quality protein and other essential nutrients including omega-3 fatty acids needed for good health. However, it may be contaminated with mercury above tolerable limits which may pose health risks to consumers especially pregnant women and the developing foetus. The aim of this study was to assess the knowledge level of pregnant women on mercury toxicity in fish on pregnancy outcomes and determine the concentration of mercury and proximate composition of smoked fish.
Methodology: This was a cross-sectional study conducted among 384 pregnant women attending Adabraka Clinic, Madina Polyclinic and Tema General Hospital. A semi-structured questionnaire was used to gather information on participant’s demographic characteristics, identify widely and frequently consumed fish and knowledge of mercury toxicity from fish consumption on pregnancy outcomes. Focus group discussion was organised among fish sellers to identify the most dominant and widely purchased fish.
The most widely consumed smoked fish species, apataa (tilapia zilli), brolovi (chrysichthys nigrodigitatus), salmon (scomber japonicas), herrings (katsuwono pelamis), tuna (Sardinella maderensis), saflo (caranx crysos), Oheneba (bagrus bayad) and red fish (entex angolensis) as reported by the pregnant women were bought from Madina, Tema and Adabraka markets and transported in polyethene bags to the laboratory for proximate analysis and determination of mercury concentration.
Results: Most (68.8%) of the participants consumed fish 5-7 meals/week. Though, more than half (57.3%) of the pregnant women who took part in this study were aware of mercury contamination of fish the majority (65.5%) of them had poor knowledge of its toxicity on pregnancy outcomes. All the analysed smoked fish species had high levels of protein, fat, fibre and ash content. The mercury concentrations of the analysed smoked fish samples were all within the recommended (0.2 μg/g wwt) allowable safe limit intake for pregnant women except apataa (0.327±0.006 μg/g) from Madina and Brolovi from Tema (0.214±0.023 μg/g) and Adabraka (0.347±0.03 μg/g). All the fish species had lower target hazard quotients (THQ) values less than 1 (THQ < 1) except apataa (1.42) and brolovi (1.50) from Madina and Adabraka markets respectively.
Conclusion: Majority of the pregnant women consumed fish 5-7 meals/week and the most frequently consumed fish was herring. More than half of the pregnant women were aware of mercury contamination in fish but majority had poor knowledge of its toxicity on pregnancy outcomes. Mercury concentration and THQ were high in apataa from Madina and Brolovi from Tema and Adabraka. The high THQ in these fishes may pose health risk to pregnant women. There is the need to educate the general public especially pregnant women on mercury contamination of fish and its possible health risk on pregnancy outcomes.
