it's not just in california, it's everywhere
a little history on known health problems with fiberglass and the use of experts to boost profits at the expense of people's health [nothing new], from
An industrial process for making glass fibers was first patented in Russia in 1840.[1, pg.292] At the Columbian Exposition in Chicago in 1893, Edward Libbey, an American, exhibited lamp shades, a dress, and other articles woven from glass fibers. In
1915, the Allied Forces blockaded Germany, creating an asbestos shortage which resulted in commercial production of fiber glass in the U.S., as an asbestos substitute. (Asbestos is a naturally-occurring fibrous material that can be woven into cloth, does not burn readily, has excellent properties for thermal insulation, and therefore came into commercial use during this century.[2, pgs.390-392] Fiber glass has many of the same characteristics as asbestos.)In 1938, the Owens Corning Fiberglas Company was formed, and three years later, in 1941, evidence of pulmonary [lung] disease was reported by Walter J. Siebert, who investigated the health of workers in cooperation with Owens Corning.[1, pg.292] That same year another investigator reported finding "no hazard to the lungs" of workers exposed to glass fibers in the air. Scientific disagreement of this sort has characterized the study of fiber glass ever since; meanwhile fiber glass production has increased steadily."
some are turning to wool now as a health conscious residential insulator