A Market Basket Survey of Horticultural Fruits for Arsenic and Trace Metal Contamination in Southeast Nigeria and Potential Health Risk Implications

Abstract

Background.Elevated arsenic and trace metal contamination of the terrestrial food chain represents one of the most significant environmental risk exposures for human populations in developing countries. Metalloid and metal contamination in horticultural crop produce such as fruit is a public health concern in Nigeria. Local fruits are cheap sources of vitamins and minerals for the resident population and pose an important dietary threat of metal(loid) toxicity through consumption.Objectives.Market basket investigation of five locally grown (guava, pineapple, orange, and pawpaw) and imported (apple) fruits was conducted to measure the total concentrations of arsenic (As), mercury (Hg), copper (Cu), and lead (Pb) present in these fruits from southeastern Nigeria (Awka, Anambra).Methods.Fruits were analyzed for As and the three metals using atomic absorption spectrophotometry. Moisture content of fruits was determined and used to transform metal concentrations in dry weight to wet weight and compared to Codex food grade standards and assorted (sub)tropical fruits, edible and inedible peels.Results.The mean ± standard deviation of elemental concentrations in dry weight ranged from 20.0±0.71–96.84±0.00 μg g−1 for As, 0.02±0.02 – 0.89±0.33 μg g−1 for Hg, 0.11±0.01 - 0.18±0.40 μg g−1 for Cu, and <0.001 – 0.03±0.05 μg g−1 for Pb. The As concentrations (wet weight) in fruits were ~32–166 orders of magnitude higher than Codex Alimentarius Commission (Codex) maximum As food grade levels. Guava and apple methyl Hg concentrations were ~6–~1 orders of magnitude higher than Codex maximum levels, while the content of Cu and Pb in fruits were within acceptable standard limits.Conclusions.The significant concentrations of As and Hg in the examined fruits indicate a potential public health threat. Efforts are needed to initiate and sustain continued monitoring of trace elements in fruits and food sold to consumers due to variation in contaminating sources to ensure food safety. Although a great deal of information exists on Hg toxicity, research on metalloids such as As remains limited in Nigeria and no reliable guidelines exist. Further research is recommended to determine the ecotoxicity of As in Nigeria.

Air Quality in Nigerian Urban Environments: A Comprehensive Assessment of Gaseous Pollutants and Particle Concentrations

“…The approach, however, is unsystematically planned to enable the sustainability of other dependent urban functions and contain spillovers. The strategic implication of this uncoordinated development is that air quality will continue to deteriorate until Anambra State realigns land-use zoning priorities and balances economic development and the environment with appropriate sustainable regulatory instruments [6,65,66]. Our results are not an isolated incident, as similar outcomes have been reported elsewhere in Southeastern Nigeria.…”

Health Risk Assessment Based on the Trace Elements in the Fruits and Vegetables Grown in an Industrial Area in Dhaka City, Bangladesh

“…On the other hand, the TTHQ was not >1, and it was concluded that all the studied fruits and vegetable were safe to consume. However, a previous study reported the heavy metal status and presence of arsenic in a rural area in Bangladesh [25], and the levels of trace metals have also been mentioned in the vegetables growing near a mining area in Andhra Pradesh (India, southeast Nigeria) [26][27][28]. Figure 6 depicts the health risk index of iron, manganese, and zinc with HI < 1.…”

Noncarcinogenic risk assessment of ten heavy metals in nine freshwater species sourced from market-ready landing sites

“…However, the maximum concentration exceeded FAO/WHO recommended limit for public health of consumers. Persistent exposure to high levels of inorganic As has severe health risk implications, including anaemia, diarrhoea, liver damage, hypertension and skin disease [17,32]. Lead (Pb) is a known hazardous metal to human health [1].…”

“…Each analytical batch of ten runs was accompanied by an acid blank and three certified reference materials (CRM). Mean recoveries were in an acceptable range (90 -99.5%) compared to the CRM theoretical or certified values for the metals [17]. Results were expressed in mg kg −1 dry weight with instrumental detection limit of 0.001 mg kg −1 dry weight and compared with FAO/WHO Codex Alimentarius (or Food Code).…”

“…On arrival at the laboratory, samples were identified and dissected with a clean knife. Edible fillet tissue of each species was collected and stored at − 20 °C prior to metals analysis [7,17].…”