A Colorado resident was bitten by a poisonous black widow spider 19 times -- and investigators are trying to figure out if the bites caused the man's death.

Black widow spider bites are poisonous, but rarely fatal, health experts told Fox31 in Denver.

Jeff Seale, 40, reportedly noticed the bites on his foot two weeks before he died. The Boulder County Coroner's Office says it could be 4-6 weeks before an official cause of death is released -- but Seale's sister is nevertheless convinced that the bites are responsible.

"I think it's definitely related. He was in really good health up until that point," she told a reporter for Fox31. "He worked at a horse stable in the evenings, and he very well could have brought one of the spiders home in his things, or picked up some stuff from one of the horse sheds and brought one of the things home," she said.

Seale, a former high-school baseball star, became obsessed with the spiders, Fox31 reported, going so far as to spray his house to prevent a spider infestation.

For more information, see the full story at Fox31 Denver.