Effects of Repeated Seafood Consumption on Urinary Excretion of Arsenic Species by Volunteers

Abstract

Arsenic (As) is a known human carcinogen and widely distributed in the environment. The main route of As exposure in the general population is through food and drinking water. Seafood harvested in Korea contains high-level organoarsenics such as arsenobetaine, arsenocholine, and arsenosugars, which are much less harmful than inorganic arsenics. However, for those who eat large amounts of seafood it is important to understand whether seafood consumption affects urinary levels of inorganic As metabolites such as arsenite, arsenate, monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA). In this study we investigated urinary As metabolites (inorganic As, MMA[V], DMA[V]) and some biological indexes such as AST, GSH, GPX, lipid peroxidation, and uric acid in volunteer study subjects (seven males and nine females). Total urinary As metabolites were analyzed by the hydride generation method, followed by arsenic speciation using HPLC with ICP-mass spectrometry. Study subjects refrained from eating seafood for 3 days prior to the first urine collection and then ingested seafood daily for 6 consecutive days. The first voided urine of the morning was collected from each subject the first day of the consecutive 6 days of seafood ingestion but prior to the first seafood meal. The first voided urine of the morning was also collected on days 1, 2, 3, 4, 5, 6, 7, 10, and 14 after seafood ingestion. The daily mean intake of total As was 6.98 mg, comprised of 4.71 mg of seaweed (67%), 1.74 mg of flat fish (25%), and 0.53 mg of conch (8%). We observed a substantial increase in total urinary As metabolites for subjects consuming seafood from day 1, which recovered to control level at day 10. The increase in total urinary As metabolites was attributed to the increase in DMA, which is a more harmful metabolite than organoarsenics. However, no significant changes in response biological indexes were observed. These results suggest that it is necessary to evaluate As metabolism when assessing the exposure to inorganic As and potential chronic health effects of seafood consumption in Korea.

Metabolic profile and assessment of occupational arsenic exposure in copper- and steel-smelting workers in China

“…Ours and others studies had reported that DMA increased signiWcantly after seafood intake (Xu et al 2008a;Choi et al 2010). In this study, workers in two plants all consumed very little seafood during 3 days prior to the study period.…”

“…In occupationally exposed subjects, the urinary excretion of As metabolites varies in accordance with the dose absorbed from the working environment, but may also be inXuenced by other sources such as food and water. The food containing As is mainly seafood, which presents high concentration of organoarsenicals, such as arsenobetaine (Choi et al 2010).…”

Arsenic in the human food chain, biotransformation and toxicology – Review focusing on seafood arsenic

“…Ingested DMA and MA seem to be excreted mainly in urine in humans, and mostly within one day [49]. Our own and others data suggest that tAs ingested with seafood is eliminated from the body within approximately four days [93,107]. Upon 15 consecutive days with blue mussel consumption, a remarkably high 12 level of urinary MA was observed.…”

“…From studies where humans have ingested seafood and the urinary excretion of arsenicals have been measured, no indications exist for formation of iAs from ingested organoarsenicals [46,49,54,85,93,99,100,143,144]. Scarce data from human seafood studies indicate that a repeated intake of seafood does not result in higher excretion of iAs than that ingested [93,107]. It is, however, not known whether urinary MA and DMA following seafood ingestion [54,93] are formed directly or via inorganic As intermediates.…”

Urinary arsenic species, toenail arsenic, and arsenic intake estimates in a Michigan population with low levels of arsenic in drinking water

“…In addition, it is worthwhile to consider the potential role of AsB because it may influence other arsenic metabolites such as DMA (Francesconi et al, 2002). Recent studies have reported higher concentrations of DMA in individuals that have consumed fish or seafood during the days before urine sample collection (Choi et al, 2010;Fillol et al, 2010;Navas-Acien et al, 2011).…”