Widespread occurrence of perchlorate in water, foodstuffs and human urine collected from Kuwait and its contribution to human exposure

Abstract

Perchlorate is a thyroid hormone-disrupting compound and is reported to occur widely in the environment. Little is known on human exposure to perchlorate in Kuwait. In this study, 218 water samples, 618 commonly consumed foodstuffs and 532 urine samples collected from Kuwait were analysed to assess the exposure of the Kuwaiti population to perchlorate. For the estimation of daily intake of perchlorate, food consumption rates were obtained from the National Nutrition Survey in the State of Kuwait (NNSSK). The results showed that leafy vegetables accounted for a major share of perchlorate exposure among the Kuwaiti population at 0.062 µg kg(-)(1) bw day(-)(1) (36.2%), followed by fruits at 0.026 µg kg(-)(1) bw day(-)(1) (15.3%) and non-leafy vegetables at 0.017 µg kg(-)(1) bw day(-)(1) (10.1%). The urinary perchlorate geometric mean (GM) concentrations ranged from 8.51 to 17.1 µg l(-)(1) for the five age groups, which were higher than those reported in other countries. The estimated urinary perchlorate exposure for the Kuwaiti general population was 0.42 µg kg(-)(1) bw day(-)(1), which was higher than that reported for the United States. The dietary intake of perchlorate for the Kuwaiti population ranged from 0.14 to 0.67 µg kg(-)(1) bw day(-)(1) for the five age groups, with a mean total daily intake of 0.17 µg kg(-)(1) bw day(-)(1) for the general population. The highest estimated dietary mean daily intake of perchlorate (0.67 µg kg(-)(1) bw day(-)(1)) was found for children at 3-5 years. The estimated dietary perchlorate exposure in Kuwait is higher than the recommended mean reference dose (RfD) but lower than that of provisional maximum tolerable daily intake (PMTDI) set by the Joint FAO/WHO Expert Committee on Food Additives (JECFA).

Trends in the Exposure, Distribution, and Health Risk Assessment of Perchlorate among Crayfish in the Middle and Lower Reaches of the Yangtze River

“…Monte Carlo-simulated risk characterization of EDIs of perchlorate through crayfish are presented in Figure 4 . Our results indicated that, for adults, the maximum EDI value of perchlorate induced by ingestion of crayfish was smaller than that for children; similar results have been found in other studies on dietary perchlorate exposure [ 29 ]. The curve for the adults showed a faster steady state than the one representing children.…”

Perchlorate – properties, toxicity and human health effects: an updated review

“…Certainly, further studies and affirmations are required to describe the correlation of goitrogen exposure and the size of newborns, as also in this case, existing reports [124][125][126][127] do not allow for the formulation of unambiguous conclusions. In addition to the studies presented in the present review, perchlorate in human urine have also been found in China [8,140], in Haiti [141] and Kuwait [142] and in maternal milk in the USA [83,143] and in human blood in China [144]. The increasing number of current perchlorate studies in various countries indicates that the perchlorate problem is still not fully understood and assessed.…”

Additives in Children’s Nutrition—A Review of Current Events

“…Perchlorate is naturally present in the environment: it occurs in the atmosphere, it is also found in soil and drinking water, and in this way, it can get into food, primarily of plant origin [ 33 , 34 ]. Additionally, it occurs as a breakdown product of chlorine disinfectants used in the process of purifying drinking water, which is another source of perchlorate in water [ 34 ].…”

“…Additionally, it occurs as a breakdown product of chlorine disinfectants used in the process of purifying drinking water, which is another source of perchlorate in water [ 34 ]. As with exposure to pesticides, diet represents the most significant route of exposure to perchlorates [ 33 , 35 ].…”

“…According to the results of a study conducted in Kuwait, the population exposure to perchlorate is estimated to be higher than in America, but still less than the reference 0.7 μg/kg body weight (BW)/day. Children aged 3–5 years are the most exposed group, and green leafy vegetables and other vegetables and fruits, respectively, are the foods with the greatest contribution to perchlorate exposure [ 33 ]. Green leafy vegetables make a significant contribution to the concentration of perchlorate in urine according to the conclusions of studies conducted in the United States of America (USA) and Austria [ 37 , 42 ].…”