ABSTRACT
Permeation of 4-chloro-2-methylphenoxyacetic acid (MCPA) in commercial herbicide formulations through common protective glove types was evaluated to aid in the selection of appropriate skin protection. The ASTM test method F739-91 was used to measure the permeation of two undiluted formulations, one containing a salt, and the other an ester form of MCPA. The four glove types tested were natural rubber, neoprene 73, nitrile 37-145, and Viton-coated chloroprene. Triplicate tests of each combination of formulation and glove material were conducted. Permeation cells with a 0.01 M sodium hydroxide collection medium were used for the experiments. Aliquots of the collection medium were withdrawn at regular intervals and acidified, and quantification of the free acid was achieved using HPLC-UV (230 nm). There was no appreciable permeation of the salt formulation over a 24-hour test period. For the ester formulation, the following mean steady-state permeation rate (microg x cm(-2) min(-1)) and mean lag time (hours), respectively, were measured: Viton (0.06, 17.8), natural rubber (0.08, 15.4), neoprene 73 (0.21, 15.1), and nitrile (0.04, 24.2). Permeation was associated with significant swelling, averaging a nearly 30 percent increase from the pre-immersion thickness. All four glove types provide adequate protection against permeation by the salt formulation and at least eight-hour protection against the ester formulation. Given the greater permeation of the ester formulation, the salt formulation of MCPA herbicide should be used whenever possible.
Subject(s)
2-Methyl-4-chlorophenoxyacetic Acid/chemistry , Gloves, Protective , Herbicides/chemistry , Occupational Health , Chloroprene , Humans , Neoprene , Nitriles , Permeability , RubberABSTRACT
The role of the birth father in adoption is debated by lawyers, adoption professionals, and members of the adoption triad. At issue is how best to involve the birth father in the adoption plan while respecting the feelings of the birth mother, prospective adoptive couple, and rights of the child. This article examines emotional, legal and practice issues related to a birth father in adoption and implications for the perinatal social worker.
