Awareness of canned-food hazards and reported canned-food practices among health-science undergraduates at a university in south-western Nigeria: a cross-sectional study

Abstract Background Canned foods are widely used in Nigeria, but little is known about how well consumers recognise canned-food-specific hazards or how they handle opened cans. We describe responses to individual questionnaire items on canned-food hazards, labelling and handling among undergraduates of a health-science college in south-western Nigeria. Methods This cross-sectional survey was conducted between January and March 2018 among 200 undergraduates of the Obafemi Awolowo College of Health Sciences, Olabisi Onabanjo University, drawn from a sampling frame of 2,613 students by proportionate stratified allocation across classes and systematic random selection within classes. A self-administered questionnaire with 30 items was used. Results are reported item by item with Wilson 95% confidence intervals (CI). Associations of sex, age and marital status with selected practices were explored with Fisher’s exact or Monte Carlo exact tests, with effect sizes and Holm adjustment across eight tests. No composite knowledge score is reported because the scoring rule cannot be verified. Results Mean age was 21.0 ± 1.7 years and 55.0% were female. Food in a dented can was correctly judged unsafe by 55.5% (95% CI 48.6–62.2); 18.5% judged it safe and 26.0% were unsure. Only 31.5% (25.5–38.2) affirmed that botulism can follow canned-food consumption (an item that did not specify improper processing). Most (85.5%; 80.0–89.7) recognised that canned foods are high in salt, and 44.0% (37.3–50.9) selected the keyed answer to a label-content item. Overall, 67.5% (60.7–73.6) reported checking expiry dates (78.9% of the 171 who answered yes or no; 29 chose “no response”). 61% (54.1–67.5) retained part of an opened can; where and how it was stored was asked in a free-text item that could not be analysed, so retention cannot be classed as unsafe. Women more often reported that nutrition information influenced purchase (79.1% versus 56.7%; odds ratio 2.89, 1.56–5.38; Holm-adjusted p = 0.006). Other associations were weak or not robust to multiple testing. Conclusions In this single-college sample surveyed in 2018, recognition of canned-food-specific hazards was uneven, and several practices could not be classed as safe or unsafe with the data collected. The instrument did not measure attitudes towards food safety. Findings are exploratory and cannot be generalised to other students or to current behaviour. Larger multi-site studies with a validated instrument, measured storage conditions and current data are needed to guide education on can inspection, post-opening storage and label literacy.