The toxic pesticide that poisoned a U.S. family on vacation in the Virgin Islands has also been improperly used in Puerto Rico , the U.S. Environmental Protection Agency said Thursday after a federal investigation . Officials said documents suggest methyl bromide may have been improperly applied in various locations in Puerto Rico . EPA regional administrator Judith Enck said the agency and Puerto Rico 's Department of Agriculture are investigating where and when the pesticide was used and how much was applied . Steve Esmond ( left ) and his wife , Dr Theresa Devine ( right ) , and their two teenage sons fell seriously ill during their stay at a resort on the island of St. John . The toxic pesticide that poisoned the family has been found in various locations in Puerto Rico , the U.S. Environmental Protection Agency said Thursday . 'The EPA is taking this very seriously , ' she said in a phone interview . ' I ca n't tell you how widespread this is ... We 're very early in our investigation . ' Sean , 16 , ( pictured ) and his 14-year-old brother Ryan remain in comas two weeks after being hospitalized due to being poisoned by methyl bromide . Enck said she is not aware of anyone sickened by methyl bromide in Puerto Rico . The EPA banned the chemical for residential use in 1984 , primarily for health concerns . Nancy Feliciano , agriculture department spokeswoman , said Puerto Rico officials would comment soon . The chemical sickened a family of four from Wilmington , Delaware , last month in the U.S. Virgin Islands . Two teenage boys went into comas after being exposed at the Sirenusa Condominium Resort in Cruz Bay , St. John . The Esmond family was staying in the second floor of a unit whose first floor was sprayed with the pesticide to eradicate an indoor beetle that eats wood , officials have said . Steve Esmond and his wife , Dr Theresa Devine , and their two teenage sons fell seriously ill during their stay . They began having seizures and were airlifted to separate hospitals in Philadelphia suffering major respiratory trauma . Sean , 16 , and Ryan , 14 , were in critical condition . Family attorney and spokesman James Maron did not respond to messages for comment . He said in a statement last week that the boys remained in critical condition while their mother had been discharged and their father was recuperating . EPA regional administrator Judith Enck said the agency and Puerto Rico 's ( pictured ) Department of Agriculture are investigating where and when the pesticide was used and how much was applied . The U.S. Environmental Protection Agency released information on the illegal use of methyl bromide after conducting a federal investigation . The EPA has said a certified applicator working for Tennessee-based Terminix used the pesticide at the Virgin Islands resort . Sea Glass Vacations LLC , which rents units at Sirenusa , terminated its contract with Terminix last week . Terminix has said it is conducting its own investigation and is cooperating with the EPA . The U.S. Justice Department also is investigating . EPA officials said Thursday the pesticide used in the Virgin Islands came from licensed distributors in Puerto Rico , where inspectors are visiting pesticide applicator companies , including Terminix . 'This has been prohibited since the 1980s , ' Enck said . 'There should be no confusion . ' Methyl Bromide , which is odorless , can be fatal or cause serious damage to the central nervous system and respiratory system , according to the EPA . It is acutely toxic , and only permitted to be used outdoors by certified professionals in the US . The family was staying at the $ 875-a-night Sirenusa Condominium Resort on St. John in the U.S. Virgin Islands when they fell ill . Methyl bromide , which was banned in the 1980s , was sprayed on the first floor of the resort the family was staying in to eradicate an indoor beetle that eats wood , officials have said .
Methyl Bromide was improperly used in U.S. Virgin Islands resort that family was staying in when they were poisoned . Score: 6