Migratory Bird Hunting; Temporary Conditional Approval of Tungsten-Matrix Shot as Nontoxic for the 1998-99 Season

Since the mid-1970s, the Service has sought to identify shot that does not pose a significant toxic hazard to migratory birds or other wildlife. Currently, only steel and bismuth- tin shot are approved by the Service as nontoxic. On October 7, 1998 tungsten-iron (63 FR 54015) and tungsten-polymer (63 FR 54021) shot were given temporary conditional approval for the 1998-99 hunting season. Compliance with the use of nontoxic shot has increased over the last few years. The Service believes that this level of compliance will continue to increase with the availability and approval of other nontoxic shot types. The Service is eager to consider these other materials for approval as nontoxic shot. The revised procedures for approving nontoxic shot (50 CFR 20.134) consist of a three-tier process whereby existing information can minimize the need for full testing of a candidate shot. However, applicants still carry the burden of proving that the candidate shot is nontoxic. By developing the new approval procedure, it was the Service's intent to discontinue the practice of granting temporary conditional approval to candidate shot material. However, the application by Kent was initiated prior to implementation of the new protocol. To date, scientific information presented in the application suggests that tungsten-matrix is nontoxic under conditions for the proposed shot configuration. Therefore, the Service will grant temporary conditional approval for the 1998-99 hunting season only. Final approval will not be granted until chronic toxicity/reproductive testing is successfully completed and the results are reviewed and approved by the Director. Kent's original candidate shot was fabricated from what is described in their application as ``* * * a mixture of powdered metals in a plastic matrix whose density is comparable to that of lead. All component metals are present as elements, not compounds. Tungsten- matrix pellets have specific gravity of 9.8 g/cm3 and is composed of 88 percent tungsten, 4 percent nickel, 2 percent iron, 1 percent copper, and 5 percent polymers by mass'' (63 FR 30044; June 2, 1998). After consultation with the Service, Kent subsequently changed the composition of their shot and removed several metal components. The new shot material being considered has a density of 10.7 g/ cm3 and is composed of approximately 95.9 percent tungsten and 4.1 percent polymers. Kent's updated application includes a description of the reformulated tungsten-matrix shot, a toxicological report (Thomas 1997), and results of a 30-day dosing study of the toxicity of the original formulation in game-farm mallards (Wildlife International, Ltd. 1998). The toxicological report incorporates toxicity information (a synopsis of acute and chronic toxicity data for mammals and birds, potential for environmental concern, and toxicity to aquatic and terrestrial invertebrates, amphibians and reptiles) and information on environmental fate and transport. The toxicity study is a 30-day dosing test to determine if the original candidate shot poses any deleterious effects to game-farm mallards. This will meet the requirements for Tier 2, as described in 50 CFR 20.134(b)(3). Because the re-formulated shot contains no new components, and in fact has had components removed, the Service determined that testing of the reformulated shot in the form of a new 30-day dosing study was not necessary. Toxicity Information: There is considerable difference in the toxicity of soluble and insoluble compounds of tungsten. Elemental tungsten, which is the material used in this shot, is virtually insoluble and is therefore expected to be relatively nontoxic. Even though most toxicity tests reviewed were based on soluble tungsten compounds rather than elemental tungsten (while the toxicity of the polymers is negligible due to its insolubility), there appears to be no basis for concern of toxicity to wildlife for tungsten-matrix shot (metallic tungsten and polymers) via ingestion by fish, birds, or mammals (Wildlife International Ltd., 1998; Bursian et al., 1996; Gigiema, 1983; Patty, 1981; Industrial Medicine 1946; Karantassis 1924). Environmental Fate and Transport: Tungsten is insoluble in water and, therefore, not mobile in hypergenic environments. Tungsten is very stable in acids and does not easily complex. Preferential uptake by plants in acid soil suggests that uptake of tungsten in the anionic form is associated with tungsten minerals rather than elemental tungsten (Kabata-Pendias and Pendias 1984). Environmental Concentrations: Calculation of the estimated environmental concentration (EEC) of tungsten in a terrestrial ecosystem is based on 69,000 shot per hectare (Pain 1990), assuming complete erosion of material in 5 cm of soil. The EECs for tungsten and the 2 polymers in soil are 25.7 mg/kg, 4.2 mg/kg, and 0.14 mg/kg, respectively. Calculation of the EEC in an aquatic ecosystem assumes complete erosion of the shot in one cubic foot of water. The EECs in water for tungsten and the 2 polymers are 4.2 mg/L, 0.2 mg/L, and 0.02 mg/L, respectively. Tungsten-matrix shot is considered insoluble and is stable in basic, neutral, and mildly acidic environments. Therefore, erosion of shot is expected to be minimal, and adverse effects on biota are not expected to occur. Effects on Birds: An extensive literature review provided information on the toxicity of elemental tungsten to waterfowl and other birds. Ringelman et al. (1993), orally dosed 20 8-week-old game- farm mallards with 12-17 (1.03g) tungsten-bismuth-tin (TBT) pellets and monitored them for 32 days for evidence of intoxication. No birds died during the trial, gross lesions were not observed during the postmortem examination, histopathological examinations did not reveal any evidence of toxicity or tissue damage, and tungsten was not detectable in kidney or liver samples. The authors concluded that TBT shot presented virtually no potential for acute intoxication in mallards. Kraabel et al. (1996) assessed the effects of embedded TBT shot on mallards and concluded that TBT was not acutely toxic when implanted in muscle tissue. Inflammatory reactions to TBT shot were localized and had no detectable systemic effects on mallard health. Nell et al. (1981) fed laying hens (Gallus domesticus) 0.4 or 1 g/ kg tungsten in a commercial mash for five months to assess reproductive performance. Weekly egg production was normal and hatchability of fertile eggs was not affected. Exposure of chickens to large doses of tungsten either through injection or by feeding, resulted in an increased tissue concentration of tungsten and a decreased concentration of molybdenum (Nell et al. 1981). The loss of tungsten from the liver occurred in an exponential manner with a half-life of

27 hours. The alterations in molybdenum metabolism seemed to be associated with tungsten intake rather than molybdenum deficiency. Death due to tungsten occurred when tissue concentrations increased to 25 mg/g liver. At that concentration, xanthine dehydrogenase activity was zero. The two plastic polymers used in tungsten-matrix shot act as a physical matrix in which the tungsten is distributed as ionically-bound fine particles. Most completely polymerized nylon materials are physiologically inert, regardless of the toxicity of the monomer from which they are made (Peterson, 1977). A literature review did not reveal studies in which either of the two polymers were evaluated for toxicity in birds. Montgomery (1982) reported that feeding Nylon 6 to rats at a level of 25 percent of the diet for 2 weeks caused a slower rate of weight gain, presumably due to a decrease in food consumption and feed efficiency. However, the rats suffered no anatomic injuries due to the consumption of nylon. Kent's 30-day dosing study on the original formulation (Wildlife International Ltd., 1998) included 4 treatment and 1 control group of game-farm mallards. Treatment groups were exposed to 1 of 3 different types of shot: 8 #4 steel, 8 #4 lead, or 8 #4 tungsten-matrix; whereas the control group received no shot. The 2 tungsten-matrix treatment groups (1 group deficient diet, 1 group balanced diet) each consisted of 16 birds (8 males and 8 females); whereas remaining treatment and control groups consisted of 6 birds each (3 males and 3 females). All tungsten-matrix-dosed birds survived the test and showed no overt signs of toxicity or treatment-related effects on body weight. There were no differences in hematocrit or hemoglobin concentration between the tungsten-matrix treatment group and either the steel shot or control groups. No histopathological lesions were found during gross necropsy. In general, no adverse effects were seen in mallards given 8 #4 size tungsten-matrix shot and monitored over a 30-day period. Tungsten was found to be below the limit of detection in all samples of femur, gonad, liver, and kidney from treatment groups. Based on the results of the toxicological report and the toxicity test of the original shot formulation (Tier 1 and 2), the Service concludes that tungsten-matrix shot, (approximately 95.9 percent tungsten and 4.1 percent polymer, by weight with xsec@ios.doi.gov.

Congressional Review

In accordance with Section 251 of the Small Business Regulatory Enforcement Fairness Act of 1996 (5 U.S.C. 8), this rule has been submitted to Congress. Because this rule deals with the Service's migratory bird hunting program, this rule qualifies for an exemption under 5 U.S.C. 808(1); therefore, the Department determines that this rule shall take effect immediately.

Paperwork Reduction Act

An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB control number. The Service has examined this regulation under the Paperwork Reduction Act of 1995 and found it to contain no information collection requirements. However, the Service does have OMB approval (1018-0067; expires 06/30/2000) for information collection relating to what manufacturers of shot are required to provide the Service for the nontoxic shot approval process. For further information see 50 CFR 20.134.

Unfunded Mandates Reform

The Service has determined and certifies pursuant to the Unfunded Mandates Act, 2 U.S.C. 1502, et seq., that this rulemaking will not impose a cost of $100 million or more in any given year on local or State government or private entities.

Civil Justice Reform--Executive Order 12988

The Service, in promulgating this rule, determines that these regulations meet the applicable standards provided in Sections 3(a) and 3(b)(2) of Executive Order 12988.

Takings Implication Assessment

In accordance with Executive Order 12630, these rules, authorized by the Migratory Bird Treaty Act, do not have significant takings implications and do not affect any constitutionally protected property rights. These rules will not result in the physical occupancy of property, the physical invasion of property, or the regulatory taking of any property. In fact, these rules allow hunters to exercise privileges that would be otherwise unavailable; and, therefore, reduce restrictions on the use of private and public property.

Federalism Effects

Due to the migratory nature of certain species of birds, the Federal government has been given responsibility over these species by the Migratory Bird Treaty Act. These rules do not have a substantial direct effect on fiscal capacity, change the roles or responsibilities of Federal or State governments, or intrude on State policy or administration. Therefore, in accordance with Executive Order 12612, these regulations do not have significant federalism effects and do not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

Government-to-Government Relationship With Tribes

In accordance with the President's memorandum of April 29, 1994, ``Government-to-Government Relations with Native American tribal Governments'' (59 FR 22951) and 512 DM 2, we have evaluated possible effects on Federally recognized Indian tribes and have determined that there are no effects.

Authorship

The primary author of this proposed rule is James R. Kelley, Jr., Office of Migratory Bird Management.

List of Subjects in 50 CFR Part 20

Exports, Hunting, Imports, Reporting and record-keeping requirements, Transportation, Wildlife. Accordingly, Part 20, subchapter B, chapter 1 of Title 50 of the Code of Federal Regulations is amended as follows:

PART 20--[AMENDED]

1. The authority citation for Part 20 continues to read as follows:

Authority: 16 U.S.C. 703-712 and 16 U.S.C. 742 a-j.

2. Section 20.21 is amended by revising paragraph (j) introductory text, and adding paragraph (j)(4) to read as follows:

Sec. 20.21 Hunting methods.

* * * * * (j) While possessing shot (either in shotshells or as loose shot for muzzleloading) other than steel shot, or bismuth-tin (97 parts bismuth: 3 parts tin with <1 percent residual lead) shot, or tungsten- iron ([nominally] 40 parts tungsten: 60 parts iron with <1 percent residual lead) shot, or tungsten-polymer (95.5 parts tungsten: 4.5 parts Nylon 6 or 11 with <1 percent residual lead) shot, or tungsten- matrix (95.9 parts tungsten: 4.1 parts polymer with <1 percent residual lead) shot, or such shot approved as nontoxic by the Director pursuant to procedures set forth in 20.134, provided that: (1) * * * (4) Tungsten-matrix shot (95.9 parts tungsten: 4.1 parts polymer with <1 percent residual lead) is legal as nontoxic shot for waterfowl and coot hunting for the 1998-1999 hunting season only, except for the Yukon-Kuskokwim Delta habitat in Alaska.

Dated: December 1, 1998. Donald J. Barry, Assistant Secretary for Fish and Wildlife and Parks. [FR Doc. 98-32470 Filed 12-7-98; 8:45 am] BILLING CODE 4310-55-P