Fish consumption, fish atopy and related heavy metals in childhood eczema.

Due to increasing worldwide water pollution, fish might be a source of excessive zinc, mercury, arsenic or  manganese  intake. The  aim  of  this  study  was  to  evaluate if  fish atopy/sensitization and fish consumption behavior are associated with eczema severity and blood levels of the 4 heavy metals. One-hundred and nineteen patients with eczema and 43 patients with miscellaneous non-eczema  skin  diseases were  studied.  There  were  no  differences  in  average weekly fish consumption  and blood  levels of  the  4 heavy metals between eczema and  non-eczema groups. Blood levels of these metals were generally within the upper limits of local reference ranges in all these patients. In eczema patients, freshwater fish consumption  behavior in days-per-week was correlated with blood arsenic and mercury levels (rho=0.17, p<0.01 for both  metals), but not  with zinc or manganese. Levels of arsenic and mercury were also correlated with days of seawater fish consumption per week (arsenic: 0.38, mercury: 0.24, p <0.05). Fish  sensitization was present  in  25%  of  patients  with eczema. Nevertheless,  there was no  difference in  terms  of  fish  consumption  behavior, eczema severity, quality of life, and  heavy metal levels between eczema patients  with or  without  fish sensitization. We  conclude  that   without   exceeding  local  normal  reference  ranges,  blood   arsenic and  mercury  levels correlated  with  fish  consumption  behavior.  There  is  no  evidence to   suggest  that   fish  sensitization  is  associated  with  more  severe  eczema  (bad  for eczema), or that patients have milder eczema with more days of fish consumption (good for eczema).