title: [Beta-hexachlorocyclohexane contamination in dairy farms of the Sacco River Valley, Latium, Italy, 2005. A retrospective cohort study].
abstract: OBJECTIVE
  in March 2005, the Italian National Monitoring System on Chemical Residuals in Food of Animal Origin detected levels of the pesticide beta-hexachlorocyclohexane (ß-HCH) that were 20 times higher than the legal limit of 0.003 mg/kg in bulk milk from a dairy farm in the Sacco River valley. ß-HCH, a lindane isomer and possible human carcinogen, was subsequently found in milk from several neighboring farms. A study was therefore undertaken to evaluate the extent and risk factors for contamination.
  
  
  METHODS
  all dairy cattle farms in the valley were enrolled in a retrospective cohort study and their bulk milk analyzed for ß-HCH. A questionnaire was administered to farmers to evaluate possible exposure factors.
  
  
  METHODS
  cases: dairy farms with at least one result indicating ß-HCH ≥ 0.002 mg/kg in bulk milk during the period april-june 2005; exposure: feeding animals on fodder cultivated in soils watered with and/or flooded by river water; participants: IZSLT, RMG Local Health Unit, FR Local Health Unit.
  
  
  METHODS
  attack rate, relative risk, attributable proportion among exposed.
  
  
  RESULTS
  of 244 farms tested, 34 met the case definition (attack rate 14%). The exposure to fodder cultivated in soils watered with and/or flooded by river water was observed in 33/34 (97%) case-farms and in 23/210 (10.9%) of those with contamination <0.002 mg/kg in bulk milk (RR 110.8; 95%CI 15.5- 792). Attributable proportion among exposed was more than 99%.
  
  
  CONCLUSIONS
  fodder cultivated near a contaminated river was the main risk factor for ß-HCH contaminated milk. On the basis of the epidemiologic evidence and laboratory testing, watering local fields with river water and production of fodder in farms with contaminated soil was banned, and all the animals from positive farms were culled.
authors.affiliation: Istituto Zooprofilattico Sperimentale delle Regioni Lazio e Toscana. marcello.sala@izslt.it
authors.forename: Marcello
authors.initials: M
authors.lastname: Sala
authors.forename: Antonino
authors.initials: A
authors.lastname: Caminiti
authors.forename: Pasquale
authors.initials: P
authors.lastname: Rombolà
authors.forename: Aldo
authors.initials: A
authors.lastname: Volpe
authors.forename: Cristina
authors.initials: C
authors.lastname: Roffi
authors.forename: Osvaldo
authors.initials: O
authors.lastname: Caperna
authors.forename: Maria
authors.initials: M
authors.lastname: Miceli
authors.forename: Alessandro
authors.initials: A
authors.lastname: Ubaldi
authors.forename: Antonio
authors.initials: A
authors.lastname: Battisti
authors.forename: Paola
authors.initials: P
authors.lastname: Scaramozzino
mesh_terms: D057914:Agricultural Irrigation; D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D002417:Cattle; D002611:Cheese / Q000032:analysis; D015331:Cohort Studies; D003612:Dairying; D005260:Female; D005506:Food Contamination / Q000032:analysis*; D001556:Hexachlorocyclohexane / Q000032:analysis*; D006722:Honey / Q000032:analysis; D006801:Humans; D050152:Intra-Abdominal Fat / Q000737:chemistry; D007558:Italy; D008452:Maximum Allowable Concentration; D008460:Meat / Q000032:analysis; D008892:Milk / Q000737:chemistry*; D010573:Pesticide Residues / Q000032:analysis*; D012189:Retrospective Studies; D045483:Rivers; D012756:Sheep; D012989:Soil Pollutants / Q000032:analysis; D014873:Water Pollutants / Q000032:analysis*
chemical_list: D010573:Pesticide Residues; D012989:Soil Pollutants; D014873:Water Pollutants; D001556:Hexachlorocyclohexane; C023888:beta-hexachlorocyclohexane