Estimation of Cadmium in Muscles of Five Freshwater Fish Species from Manzalah Lake, and Possible Human Risk Assessment of Fish Consumption (Egypt)

Abstract

The Egyptian government devised a plan in 2016 to improve the unique ecological significance of northern lakes, which mentioned Manzalah Lake in the Egypt Vision 2030. In this regard, this study investigated cadmium (Cd) content in five freshwater fish species collected from Manzalah Lake in Egypt at 2018 by local fishermen. According to the findings, Clarias gariepinus recorded the highest concentration of Cd (1.40 ± 0.2 μg/g) and the lowest concentration was recorded in O. aureus (1.19 ± 0.2 μg/g). Cadmium contents of all species were largely above the permissible level of the Food Agricultural Organization (FAO)/World Health Organization (WHO) and Commission Regulation (EC). The estimated daily intake (EDI), the estimated weekly intake (EWI), and the percentages of provisional tolerable weekly intake (PTWI %) values for Cd in the C. gariepinus > Sarotherodon galilaeus > Tilapia zillii > Oreochromis niloticus > Oreochromis aureus which consumed by children, teenagers, and adults were much higher than the PTWI values established by FAO/WHO. In addition, C. gariepinus consumed by children showed the highest value of the target hazard quotient (THQ) (5.83 a day or 40.81 a week) while O. aureus that ingested by adults showed the lowest level (1.06 a day or 7.42a week). The target carcinogenic risk (TCR) of C. gariepinus in children had the greatest level (2.21 × 10−3 a day or 1.55 × 10−2 a week), whereas O. aureus in adults had the lowest level of TCR (4 × 10−4 a day or 2.81 × 10−3 a week). THQs values of Cd in the five studied species were found higher than one. Moreover, TCRs values of Cd in the five species were exceeded the US Environmental Protection Agency guideline USEPA permissible limits suggesting that a daily or weekly consumption of these species could lead to a high risk non-carcinogenic and carcinogenic for humans.

Metals and Metalloid Concentrations in Fish, Its Spatial Distribution in PPC, Philippines and the Attributable Risks

“…Only As was included in the CR calculation as it was the only MM in this study that was identified by the IARC as a carcinogen [ 58 ]. It was shown in the Table that the CR of the brackish water fish was 0, which was lower than the threshold value of indicating a negligible risk of developing cancer [ 42 , 44 ]. The CR of the marine water fish was which was also lower than the threshold value of indicating negligible risk of developing cancer [ 42 , 44 ] from the consumption of marine water fish.…”

“… where CDI is the chronic daily intake of MMs (mg kg −1 day −1 ) and SF is the slope factor (mg kg −1 day −1 ), as shown in Table 1 [ 38 ]. Cancer risk is categorized as negligible if CR < 1 × 10 −6 ; acceptable if CR is within 1 × 10 −6 –1 × 10 −4 ; high if CR is within 1 × 10 −3 –1 × 10 −1 ; and very high if CR > 1 × 10 −1 [ 44 ].…”

“…It was shown in the Table that the CR of the brackish water fish was 0, which was lower than the threshold value of 1 × 10 −6 indicating a negligible risk of developing cancer [42,44]. The CR of the marine water fish was 1.38 × 10 −8 which was also lower than the threshold value of 1 × 10 −6 indicating negligible risk of developing cancer [42,44] from the consumption of marine water fish. Table 4 shows the maximum allowable fish consumption rates (CR lim ) that a 60 kg adult can consume in a day.…”