Arsenic methylation by micro-organisms isolated from sheepskin bedding materials

Sudden infant death syndrome (SIDS) has been associated with the volatilization of arsenic, antimony or phosphorus compounds from infants' bedding material by micro-organisms, the so-called ‘toxic gas hypothesis’. The volatilization of arsenic by aerobic micro-organisms isolated from new sheepskin bedding material, as well as on material used by a healthy infant and by an infant who perished of SIDS, was examined. Three fungi were isolated from a piece of sheepskin bedding material on which an infant perished of SIDS, which methylated arsenic to form trimethylarsenic(V) species, precursors to volatile trimethylarsine. These three fungi were identified as Scopulariopsis koningii, Fomitopsis pinicola and Penicillium gladioli by their 26S-ribosomal RNA polymerase chain reaction products. These fungi were not previously known to methylate arsenic. The volatilization of arsenic by these three fungi was then examined. Only P. gladioli volatilized arsenic and only under conditions such that the production of sufficient trimethylarsine to be acutely toxic to an infant is unlikely. S. brevicaulis grew on the sheepskin bedding material and evolved a trace amount of trimethylarsine. Known human pathogens such as Mycobacterium neoaurum and Acinetobacter junii were isolated from used bedding.

Download Full-text

Cosleeping and Sudden Unexpected Death in Infancy

Archives of Pathology & Laboratory Medicine ◽

10.5858/2002-126-0343-casudi ◽

2002 ◽

Vol 126 (3) ◽

pp. 343-345

Author(s):

Tiffany L. A. Person ◽

Wendy A. Lavezzi ◽

Barbara C. Wolf

Keyword(s):

Sudden Infant Death Syndrome ◽

Sudden Infant Death ◽

Sudden Unexpected Death ◽

Sudden Infant ◽

Unexpected Death ◽

Infant Deaths ◽

The Subject ◽

Bedding Materials ◽

Mechanical Asphyxia

Abstract Context.—The practice of infants cosleeping with adults has long been the subject of controversy. Autopsy findings in cases of sudden infant death syndrome (SIDS) are usually indistinguishable from those found with unintentional or intentional suffocation, and the determination of the cause of death in cases of sudden unexpected death in infancy is often based on investigative findings and the exclusion of natural or traumatic causes. Objective.—To further elucidate the risk of cosleeping. Methods.—We reviewed 58 cases of sudden unexpected infant deaths. Cases were excluded if there was any significant medical history or evidence of trauma or abuse. Results.—Twenty-seven of the infants were cosleeping. Eleven of these cases had been previously diagnosed as SIDS, and in 7 cases parental intoxication was documented. Conclusion.—Our findings support recent studies that suggest that cosleeping or placing an infant in an adult bed is a potentially dangerous practice. The frequency of cosleeping among cases diagnosed as SIDS in our study suggests that some of these deaths may actually be caused by mechanical asphyxia due to unintentional suffocation by the cosleeping adult and/or compressible bedding materials.

Download Full-text