Document KRvvjjJLgQMe356OZBXLj379r

nd fi Meeting of CTFA Task Force on Round Robin Testing of Consumer Talcum Product fosr Asbestiform Amphibole Minerals . May 17 1977 CTFA Headquarters Thus far no company has called to ask if their product was reported positive It is the responsibility of this Task Force to meet two objectives 1. Determine whether or not any 1976 production major commercial talc products contain asbestiform amphibole contaminants 2. Test and verify CTFA Method J4-1 for this purpose - and assurance that method is accurate reliable practical These objectives have not yet been achieved | Proposal A partial round robin retest - sets of 4 samples to be coded and submitted to participating labs at random to include 1 - standard probably talc spiked with CTFA tremolite 3 - products indicated by several labs to be positive - 33 5 # Code to remain in my possession ~ # every Recommendations 1. Method J4-1 Part I - leave as is for partial retest Future - Must make specific mention of higher limit of detection for anthophyllite - Possibly increase sensitivity for tremolite to about 0.2 narrow scanning range for tremolite anthophyllite specifically - Have copies of curve showing differences of ray response to massive and fibrous meeting tremolite Will distribute at if necessary only JNJ 000250613 -2- | 2. Perform partial retest using TENTATIVE REVISION for Method J4-1 Part II - instructions are more precise and clear incorporates suggestions from McCrone other microscopists REVISION is based on current expertise and availability of amphibole standards 3. Retain OSHA Field Memorandum as fiber definition for partial retest and until government promulgates new definition Our purpose is not to redefine fiber 4. As retest results come in if some labs still report asbestiform amphibole Schelz to contact individually to request training of microscopist JNJ 000250614