Formation of toxic arsenical in roasted muscles of marine animals

Abstract

Arsenobetaine, an organo-arsenic compound known to be non-toxic, occurs ubiquitously in marine animals. To elucidate the food hygiene safety of the degradation products of arsenobetaine formed on cooking, arsenicals generated by roasting the muscles of the starspotted shark Mustelus manazo and of the red crayfish Panulirus longipes femoristriga were investigated. As a result, both muscle types were found to contain the tetramethylarsonium ion, which is reported to show a higher acute toxicity than dimethylarsinic acid (cacodylic acid) or methanearsonic acid. As a minor compound, arsenate was also detected in the muscle of M. manazo.

Scientific Opinion on Arsenic in Food

“…Additionally, arsenic species can be converted to other arsenicals during food preparation. In general, these changes are not great, but they can be significant after cooking at high temperatures, such as might be reached on the surface of the food during frying or grilling (Hanaoka et al, 2001;Torres-Escribano et al, 2008).…”

“…Dahl et al (2009) also observed that the concentrations of tetramethylarsonium ion increased from their initial low values when samples of both fresh and frozen seafood were fried. This result supported the earlier work of Hanaoka et al, 2001 who showed that when seafood is cooked at high temperatures, a portion of the arsenobetaine present can convert to tetramethylarsonium ion. Perelló et al (2008) evaluated the effects of traditional cooking processes (frying, grilling, roasting and boiling) on the concentration of total arsenic and several other elements in a number of food samples, especially of animal origin.…”

“…This process takes place at temperatures above 150°C, and can be significant in some cooking treatments in which the surface of the food is in direct contact with the heat source and reaches temperatures close to 250°C, such as roasting, grilling or baking. Hanaoka et al (2001) were the first to observe this conversion in roasted shark and crayfish. In contrast, cooking seafood in water (stewing, boiling, or steaming) does not convert arsenobetaine to tetramethylarsonium ion .…”

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

“…Generally, the pattern of arsenicals does not seem to be altered much due to processing, however, most seafood processing studies have found an increase in TETRA after heat application [154][155][156][157]. Since TETRA is considered to be more toxic than AB, the increase in TETRA in seafood processed at high temperatures should be taken into account when assessing the safety of such products [128].…”

“…[154][155][156][157] However, we found that cooking in water (stewing, boiling or steaming) did not decrease the content of AB [154]. One previous study has also indicated that AB can be degraded in an oxidative environment [158].…”