Exploring potential dietary contributions including traditional seafood and other determinants of urinary cadmium levels among indigenous women of a Torres Strait Island (Australia)

Abstract

Indigenous people of the Torres Strait Islands have been concerned about the safety of their traditional seafoods since the discovery of high cadmium levels in the liver and kidney of dugong and turtle in 1996. This study explored links between urinary cadmium levels and consumption frequency of these traditional foods and piloted a community-based methodology to identify potential determinants of cadmium exposure and accumulation. Consultations led to selection of one community for study from which 60 women aged 30 to 50 years participated in health and food frequency survey, urine collection and a routine health check. Urinary cadmium levels were determined by inductively coupled plasma-mass spectrometry; data were analysed using SPSS-14. The geometric mean cadmium level in this group of women was 1.17 (arithmetic mean 1.86) mg/g creatinine with one-third exceeding 2.0 mg/g creatinine. Heavy smoking (Z300 pack years) was linked to higher cadmium in urine, as was increasing age and waist circumference. Analysis of ageadjusted residuals revealed significant associations (Po0.05) between cadmium level and higher consumption of turtle liver and kidney, locally gathered clams, peanuts, coconut, chocolate and potato chips. Dugong kidney consumption approached significance (P ¼ 0.06). Multiple regression revealed that 40% (adjusted r 2 ) of variation in cadmium level was explained by the sum of these associated foods plus heavy smoking, age and waist circumference. No relationships between cadmium and pregnancy history were found. This paper presents a novel approach to explore contributions of foods and other factors to exposure to toxins at community level and the first direct evidence that frequent turtle (and possibly dugong) liver and kidney and wild clam consumption is linked to higher urinary cadmium levels among Torres Strait Islander women.

Dietary predictors of urinary cadmium among pregnant women and children

“…Additional findings unique to our study include the marginal contribution of avocado to UCd. Potato marginally contributed to UCd, as seen in prior studies (Haswell-Elkins et al 2007). Findings in children suggest that consumption of pizza and potatoes, foods indicative of the nutrition transition, could have contrasting impacts on dietary contributions to cadmium exposure.…”

Sources of cadmium exposure among healthy premenopausal women

“…We found evidence suggesting that eating leafy greens, green salad, yams, cooked cereals, and vegetable soups was associated with uCd. However, we did not observe an association between uCd and “peanut butter, peanuts, and other nuts or seeds”, shellfish, potatoes, rice, or carrots, as might have been anticipated (Egan et al, 2007; Egan et al, 2002; Haswell-Elkins et al, 2007; Hellstrom et al, 2007; Vahter et al, 1996). Liver and other organ meats were not eaten regularly enough by study participants to draw reliable conclusions.…”

“…Among non-smokers, direct measurements of cadmium in foods indicate that leafy green vegetables, grains, shellfish, root vegetables, legumes, seeds and nuts, and organ meats are typically considered to be the most significant dietary sources of cadmium (Egan et al, 2007; Egan et al, 2002). However, there is limited empiric data comparing measurement of urine cadmium (uCd) with reported routine consumption of potential dietary sources (Haswell-Elkins et al, 2007; Hellstrom et al, 2007; McElroy et al, 2007a; Satarug et al, 2010; Vahter et al, 1996). …”

Cadmium exposure and endometrial cancer risk: A large midwestern U.S. population-based case-control study

“…Heavy smokers may have twice as much cadmium, and moderate smokers’ cadmium burden may increase by approximately sixty percent compared to non-smokers [9]. Former smokers have a cadmium body burden that is intermediate [24,41].…”

“…Tobacco plants readily take up agricultural sources of cadmium [8]. A doubling of urinary cadmium levels may be found in heavy smokers (>300 pack years (number of smoking years times usual number of cigarettes per day)) compared to non-smokers [9]. …”