|
CFSAN/Office of Food Additive Safety
May 5, 2003
Date: May 5, 2003
From: Environmental Toxicologist, Environmental Review Group (ERG)
Division of Chemistry Research and Environmental Review (HFS-246)
Subject: FCN No. 327 - Polypropylene glycol monobutyl ether for use as a diluent for defoamers used in the pulping of lignocellulosic materials used to make paper and paperboard
Notifier: Crompton Corporation
771 Old Saw Mill River Road
Tarrytown, NY 10591
To: Division of Food Contact Notifications (HFS-275)
Attention: William J. Trotter, Ph.D.
Through: Layla I. Batarseh, Ph.D., Supervisor, ERG
Attached are the Finding of No Significant (FONSI) and our supplement to the notifier's Environmental Assessment for FCN 327. When this notification becomes effective, these documents and the notifier's Environmental Assessment, dated March 13, 2003, may be made available to the public.
Please let us know if there is any change in the identity or use of the food-contact substance.
Tong Zhou, Ph.D.
2 Attachments
A food contact notification (FCN No. 327), submitted by Crompton Corporation, to provide for the safe use of polypropylene glycol monobutyl ether as a diluent in defoamers used in the pulping of lignocellulosic materials that will be used to make food-contact paper and paperboard.
The Environmental Review Group has determined that allowing this notification to become effective will not significantly affect the quality of the human environment and therefore will not require the preparation of an environmental impact statement. This finding is based on information submitted by the notifier in an environmental assessment (EA) dated March 13, 2003, and on our supplement to that EA.
Prepared by___________________________________________ Date: May 5, 2003
Tong Zhou, Ph.D., Environmental Toxicologist
Environmental Review Group
Division of Chemistry Research and Environmental Review
Office of Food Additive Safety
Center for Food Safety and Applied Nutrition
Food and Drug Administration
Approved by___________________________________________ Date: May 5, 2003
Layla I. Batarseh, Ph.D., Supervisor
Environmental Review Group
Division of Chemistry Research and Environmental Review
Office of Food Additive Safety
Center for Food Safety and Applied Nutrition
Food and Drug Administration
This document incorporates by reference the notifier's environmental assessment (EA) dated March 13, 2003.
Under Format Item 8 of the EA, the notifier, Crompton Corporation, concluded that the potential release of the food contact substance (FCS) is not expected to result in any significant environmental effects based solely on the low levels at which the substance may be introduced into the environment. The notifier did not adequately support such a conclusion by providing actual ecotoxicity data for either the FCS or closely related substances, or by estimating ecotoxicity endpoints using structure-activity relationships (SAR) predication models. In a letter dated April 15, 2003, the notifier provided only a single value for acute toxicity for one species of benthic amphipod, namely a published LC50 value of 17 mg/l (ppm) for G. fasciatus for Stabilene (a commercial name for the FCS) .
It is not always true that a low level at which a substance is introduced into the environment means low ecotoxicity of the substance, especially if the substance does not biodegrade, but rather accumulates in the environment. Consequently, we have prepared this supplement to the EA to discuss further the environmental exposure, fate, and effects of this FCS.
Introduction of Substances into the Environment as a Result of Use/Disposal
If the pulp slurry contains 0.5% pulp, the notifier calculated (on page 6 of the EA) the environmental introduction concentration (EIC) of the FCS in white water or paper mill effluent to be 0.8 ppb; a worst case estimate of the expected environmental concentration (EEC) of the FCS in receiving water is 0.08 ppb, using conservative dilution factor of 10. Typically, the pulp is dispersed at a consistency of approximately 0.5% to 1%. Using 1% pulp in the pulp slurry, we calculated the EIC in paper mill effluent to be 1 ppb, and the EEC in receiving water to be 0.1 ppb as a worst case estimate.
Structure-Activity Relationship Analysis
The chemical formula for the FCS is C4H9O(C3H6O)11.7H (M.W. = 750 Daltons). We have conducted environmental fate and ecotoxicity analysis for a closely related substance C4H9O(C3H6O)11H (M.W. = 713 Daltons), using EPI SuiteTM (v3.10) SAR predication models . Based on the predicated data, we arrived at the following conclusions:
1. The FCS has little potential to bioaccummulate because of the low predicated values of Kow (logKow=2.42) and bioconcentration factor (BCF=14.47).
2. The FCS will undergo primary biodegradation in weeks.
3. Acute and chronic toxicities of this FCS are not expected to occur at the worst-case estimates of the environmental concentrations of the substance. The lowest predicated toxicity endpoint is 14 ppm (16-day EC50 for Daphnid); this value is more than five orders of magnitude higher than the worst case estimated EEC of 0.1 ppb.
Conclusion
Based on the small introduction of the FCS to aquatic environments, little potential to accumulate in the environment, and little potential to bioaccumulate in the living organisms, we believe that there would be no potential for significant adverse environmental impacts due to the expected release of this FCS into the environment as proposed in FCN 327.
Prepared by_____________________________________________ Date: May 5, 2003
Tong Zhou, Ph.D., Environmental Toxicologist
Environmental Review Group
Division of Chemistry Research and Environmental Review
Office of Food Additive Safety
Center for Food Safety and Applied Nutrition
Food and Drug Administration
