"Published Occasionally at Irregular Intervals"
Arthur L. Craigmill
"IN THIS ISSUE"
- Poisoning by an Illegally Imported Chinese Rodenticide Containing Tetramethylenedisulfotetramine New York City, 2002
- Veterans and Agent Orange: Update 2002
- Treated Lumber Can Be Recycled to Preserve Forests, Landfills
- If You Use Manure in Your Garden, Take Precautions
- Salmonellosis Outbreak Prompt Alfalfa Sprout Recall
- DPR Announces "Right-To-Know" Initiative, Releases Illness Data
- DPR Proposes New Regulations to Protect Ground Water
- Prevalence of Current Cigarette Smoking Among Adults and Changes in Prevalence of Current and Some Day Smoking - United States, 1996-2001
- Illegal Pesticide Products
Illegally imported foreign products can result in domestic
exposures to unusual toxic chemicals, and health-care providers might
not be able to provide appropriate therapy because the chemical ingredients
might not be listed or recognized even after translation of the product
label. This report describes the first known case in the United States
of exposure to a Chinese rodenticide containing the toxin tetramethylenedisulfotetramine
(TETS), a convulsant poison. The report of this investigation highlights
the need to prevent such poisonings through increased public education,
awareness, and enforcement of laws banning the importation of illegal
On May 15, 2002, a previously healthy female infant aged 15 months living with her family in New York City was found by her parents to be playing with a white rodenticide powder that they had brought from China and applied in the corner of their kitchen. After 15 minutes, the child had generalized seizures and was taken to an emergency department. Despite aggressive therapy with lorazepam, phenobarbital, and pyridoxine, she had intermittent generalized seizure activity for 4 hours and required intubation. After 3 days, the infant was extubated successfully but appeared to have multiple neurologic deficits, including absence seizures and possibly cortical blindness. The infant was discharged in June; as of November 5, the infant remained severely developmentally delayed and was on valproic acid therapy for seizure control.
Translation of the rodenticide package labeling from Chinese to English did not clarify its contents (see Figure 1 below). A search of the China National Poison Control Center's (NPCC) website for rodenticides suggested that the ingredients might have included sodium monofluoroacetate, fluoroacetamide, tetramethylenedinitrosotetramine, or strychnine. However, an initial laboratory analysis was negative for sodium fluoroacetate, fluoroacetamide, bromethalin, strychnine, 1,3-difluoro, 2-propanol, and carbamate insecticides.
On September 14, a snack shop owner in China poisoned food in a competitor's snack shop with a rodenticide identified as Dushuqiang, resulting in 38 deaths. Although Dushuqiang, which contains TETS, has been banned for sale since the mid-1980s, it is still widely available in China. Following news reports of this incident, the New York City Poison Control Center conducted additional laboratory testing of the product associated with the poisoning in New York City and confirmed TETS in the product by gas chromatography-mass spectrometry (GC-MS). TETS concentration was 6.4% weight/weight [w/w] in one rodenticide packet and 13.8% w/w in another.
Editorial Note: TETS is a little-known, often unrecognized, and highly lethal neurotoxic rodenticide that once was used widely. An odorless, tasteless, and water-soluble white crystalline powder that acts as gamma-amino butyric acid (GABA) antagonist, TETS, like picrotoxin, binds noncompetitively and irreversibly to the GABA receptor on the neuronal cell membrane and blocks chloride channels. The most common routes of exposures are through ingestion and inhalation. TETS is not registered by the U.S. Environmental Protection Agency for use in the United States, and its importation, manufacture, and use in the United States are illegal.
TETS meets criteria for inclusion in the list of extremely hazardous pesticides maintained by the World Health Organization (WHO) and is more lethal than WHO's most toxic registered pesticide, sodium fluoroacetate. Multiple large intentional and unintentional exposures in China have demonstrated the human toxicity of TETS. The dose at which TETS kills 50% of mammals (LD50) is 0.1-0.3 mg/kg; a dose of 7.0-10.0 mg is considered lethal in humans. TETS is potentially 100 times more toxic to humans than potassium cyanide and might be a more powerful human convulsant than strychnine.
The most recognizable clinical signs after a TETS exposure are refractory seizures. Other potentially serious signs include coma and possible electrocardiogram evidence of ischemia. Symptoms typically begin within 30 minutes after exposure and can begin as long as 13 hours after exposure. Severe poisonings are usually fatal within 3 hours. TETS intoxication is determined rapidly from history and clinical suspicion. TETS is registered with the Chemical Abstract Service Division of the American Chemical Society as number 80-12-6, molecular weight 240, and chemical formula of C4H8N4O4 S2. Every attempt should be made to identify this chemical if it is suspected.
No proven antidote exists for TETS poisoning. Treatment should follow accepted modalities for a poisoned, altered, or seizing patient. Universal precautions should be taken to prevent secondary exposure of health-care workers. If TETS is suspected, regional poison control centers can provide information and guidance. A small study of rodents conducted in China suggested that intravenous pyridoxine and dimercaptosuccinic acid might be effective treatments. In China, charcoal hemoperfusion and hemodialysis are used to provide extracorporeal removal in patients poisoned with TETS.
This is the first known case of TETS poisoning in the United States. The chemical's morbidity and lethality and the lack of a known antidote present a danger to human health in areas where TETS might be imported illegally, especially large urban areas with substantial immigrant populations. The appearance of a banned or illegal substance presents challenges to regulatory and enforcement agencies because of the increased risk for unintentional and intentional exposures. Poisoning caused by TETS exposure can be prevented with heightened public health education, increased awareness, and adequate enforcement by customs, border, and regulatory agencies.
REF:Centers for Disease Control and Prevention Morbidity and Mortality Weekly Report, March 14, 2003 / 52(10);199-201
A re-evaluation of evidence now supports an association between exposure to herbicides used during the Vietnam War and the development of a specific form of leukemia in veterans, says a new report from the Institute of Medicine (IOM) of the National Academies. The report is the latest update in a series examining the health effects of defoliants – including Agent Orange - and chemicals that contaminate them.
As part of its biennial update, the committee that
wrote the report reassessed six studies of herbicide exposure that provided
information on chronic lymphocytic leukemia (CLL) among other health effects.
The reexamination revealed sufficient evidence of an association between
exposure to chemicals sprayed in Vietnam and risk of developing CLL.
In previous updates on the health risk to veterans posed by exposure to Agent Orange and other chemicals used in Vietnam, IOM had considered all forms of leukemia collectively when examining research on links between herbicide exposure and risk of cancer. The combined evidence was found to be inadequate or insufficient to determine whether any association exists between leukemia and exposure to the herbicides or their contaminants. However, although classified as a form of leukemia, CLL shares many traits with Hodgkin’s disease and non-Hodgkin’s lymphoma, both of which previously have been found to be associated with herbicide exposure. Both CLL and lymphoma originate from malignant Bcells, and CLL can transform into an aggressive non-Hodgkin’s lymphoma known as Richter’s Syndrome.
“The similarities between CLL and lymphoma—which
we have long known to be associated with exposure to the types of chemicals
used in Agent Orange and other defoliants—began to raise questions about
whether CLL should be considered separately from other forms of leukemia,”
said committee chair Irva Hertz-Picciotto, professor of epidemiology,
University of North Carolina, Chapel Hill, and University of California,
Davis. “At the request of the Department of Veteran Affairs, we looked
into the matter, and our reassessment indicates that CLL is indeed a
special case. The data are sufficient to support a link between herbicide
exposure and this type of cancer.”
The committee’s new assessment of CLL is based on evidence from six studies that looked at cancer rates, including specific forms of leukemia, and other health effects among agricultural workers exposed to herbicides, as well as individuals who reside in agrarian settings. The risk for CLL was found to be elevated in those whose occupations involved handlings of or exposure to the types of herbicidal chemicals also used during the Vietnam War.
The ability of researchers to pinpoint the health risks faced by individual veterans is hampered by inadequate information about exposure levels of troops in Vietnam. Most information comes from studies of civilians who have been exposed on the job or in industrial accidents to herbicides or their contaminants. However, most veterans probably experienced lower levels of exposure than people who have worked with these chemicals over long periods in occupational or agricultural settings, and it is difficult to say precisely which troops may have been exposed to larger amounts.
CLL is the most common form of leukemia, with roughly
7,000 new cases diagnosed in the United States last year. However, it
is among the rarer forms of cancer, making it difficult to do large-scale
studies to determine causes. There are no accurate estimates of how
many Vietnam veterans have been diagnosed with CLL.
The committee’s congressionally mandated report also reaffirms findings from previous IOM updates. In addition to non-Hodgkin’s lymphoma, Hodgkin’s disease, and now CLL, there is sufficient evidence of a link between exposure to chemical defoliants or their contaminants and the development of soft-tissue sarcoma and chloracne in veterans. Also, scientific studies continue to offer limited or suggestive evidence of an association with other diseases in veterans—including Type 2 diabetes, respiratory cancers, prostate cancer, and multiple myeloma—as well as the congenital birth defect spina bifida in veteran’s children.
U.S. forces sprayed Agent Orange and other defoliants over parts of south Vietnam and Cambodia beginning in 1962. Most large-scale sprayings were conducted from airplanes and helicopters, but considerable quantities of herbicides were dispersed from boats and ground vehicles or by soldiers wearing back-mounted equipment. A 1969 scientific report concluded that one of the primary chemicals used in Agent Orange could cause birth defects in laboratory animals. The U.S. military therefore suspended the use of Agent Orange in 1970 and halted all herbicide spraying in Vietnam the following year. The committee’s work is sponsored by the U.S. Department of Veterans Affairs.
Read the full text of Veterans and Agent Orange: Update 2002 for free on the Web as well as over 2,500 other publications from the National Academies. Printed copies will be available for purchase from the National Academies Press; tel. (202) 334-3313 or 1-800-624-6242 or on the Internet at http://www.nap.edu. (Food Industry Environmental Network e-mail update, January 28, 2003)
REF: Pesticide Reports, Oklahoma State Cooperative
Extension, March 2003.
The use of Chromated Copper Arsenic (CCA) treated wood
has garnered a great deal of media attention over the past few years
due to possible environmental and public safety concerns. "Another concern
of this material has just recently gained attention from researchers,
environmentalists, and government organizations," says Bob Smith, Virginia
Tech's wood science and forest products associate professor in the
College of Natural Resources. "That is the amount of CCA-treated wood
being removed from people's homes and businesses and going to the nation's
Chromated Copper Arsenate, or CCA as it is commonly known, is the chemical compound used to pressure treat wood in order to resist attack from insects and decay. Smith explains that CCA can typically extend the life of wood in an outdoor environment by 30 to 40 years, thus saving the forest resource. “Since the early 1970's, CCA-treated wood has been used in approximately 80 percent of residential decks built in the United States,” Smith states.
The Environmental Protection Agency (EPA) and the wood preserving industry have voluntary removed the use of CCA for the treatment of wood in residential applications starting in January 2004. "This will end much of the media hype in the possible adverse side affects that CCA may produce because of the arsenic in its formulation," predicts Virginia Tech's wood science research assistant, Dave Bailey. "However, another concern is the amount of CCA-treated wood that could end up in landfills, especially from residential decks. Several researchers across the country have indicated that the amount of discarded CCA-treated wood reaching landfills is increasing and the tonnage is expected to rise substantially over the next several decades."
Research performed at Virginia Tech by the wood science and forest products department and the USDA Forest Service in Blacksburg, Va., have estimated that 1 billion board feet of CCA-treated wood is removed from residential decks and disposed primarily in landfills each year. Researchers from other universities have examined the possible leaching of CCA chemicals from wood in to unlined landfills, in hopes to determine if the rate of CCA chemical leachate will contaminant groundwater supplies. "This research could cause tighter regulations on the disposal of CCA-treated wood, and force the cost of disposing old decks to increase over the next few years," explains Smith.
To help reduce the burden on landfills and the demand of timber harvested for use by the wood industry, research is being conducted at the Brooks Forest Products Laboratory at Virginia Tech to extend the useful life of used CCA-treated material. This research has evaluated the amount of useful material that a deck contains, which instead of ending up in a landfill could be re-used.
'The research has calculated the amount of CCA-treated wood in a residential deck prior to demolition, and then determined the amount of usable CCA-treated material capable of being recycled," notes Bailey. "We have determined that over 80 percent of a discarded CCA-treated deck can be recovered into useable lumber such as 5/4” radius edge decking, 1”x6” boards and 2”x4”, 2”x6”, and 2”x8” lumber."
The physical and mechanical properties of the spent CCA-treated wood were also evaluated, to verify if this used material can perform to needed standards. The chemical retention levels (the amount of chemicals in the wood) of the used CCA-treated wood were similar to that of new CCA-treated wood found in many local home improvement centers. The strength of the old wood was also tested for comparison to new CCA-treated wood. The mechanical tests concluded that the strength properties of the discarded CCA-treated wood, destined for the landfill, were similar as new CCA-treated wood.
A variety of products were made from the used CCA-treated wood that could be easily produced by the deck owner, recycling companies, or local community organizations. Some of the products manufactured included different residential decks and deck components, such as railings, steps, or posts, trellises, trash can containers, pallets, and outdoor furniture such as chairs, benches, porch swings, and utility tables. The new guidelines regarding CCA for treated lumber does not affect wood currently in service. The EPA has suggested that the lumber be coated with a protective barrier if small children will be be exposed to the material. EPA recommends an oil-based transparent stain be applied on a regular basis. For more information on the ruling, visit the website (www.epa.gov/pesticides/factsheets/).
Other products that could also be produced are landscaping components, such as planter boxes, raised flowerbeds, and retaining walls, material for parks and recreation facilities, such as sign posts, trial guides, and walking bridges. Many homeowners, community organizations, and governments could find the products made from used CCA-treated wood of equal quality compared to using new CCA-treated wood, and more cost effective.
Smith says, “We are currently evaluating what it would take for landfill managers to be willing to separate out the CCA-treated wood to sell or donate to parties that could recycle the materials into the useable products we have identified. Our research has helped to recognize the potential of discarded CCA-treated wood. It could certainly reduce the burden on landfills and lessen the demand of our forests by extending the life of current forest products.”
Tobacco use, particularly cigarette smoking, is the leading preventable cause of death in the United States and is responsible for approximately 440,000 deaths each year. One of the national health objectives for 2010 is to reduce the prevalence of cigarette smoking among adults to <12%. To examine the prevalence of smoking for the 50 states, the District of Columbia (DC), Guam, Puerto Rico, and the Virgin Islands, CDC analyzed data from the 2001 Behavioral Risk Factor Surveillance System (BRFSS). This report summarizes the results of that analysis, which indicate that, during 2001, the median adult current smoking prevalence was 23.4% for the states and DC, and 12.5% for Guam, Puerto Rico, and the Virgin Islands. During 1996-2001, the prevalence of current smoking was relatively stable in 41 states and DC, and the proportion of current smokers who were some day smokers increased significantly in 31 of those states and DC. "Current smokers" were defined as those who reported having smoked >100 cigarettes during their lifetime and who currently smoked every day or some days. "Some day" smokers were current smokers who responded that they smoked some days. Data on current smoking have been available since 1996. Because the only safe alternative to smoking is cessation, interventions should target all smokers to help them quit smoking completely.
In 2001, the median prevalence of current smoking in the 50 states and DC was 23.4%. Prevalence was highest in Kentucky (30.9%), Oklahoma (28.8%), West Virginia (28.2%), Ohio (27.7%), Indiana (27.5%), Nevada (27.0%), South Carolina (26.2%), and Alaska (26.1%), and lowest in Utah (13.3%), California (17.2%), Massachusetts (19.7%), Idaho (19.7%), Nebraska (20.4%), Oregon (20.5%), Hawaii (20.6%), Connecticut (20.8%), and DC (20.8%). Current smoking prevalence was 9.8% in the Virgin Islands, 12.5% in Puerto Rico, and 31.4% in Guam.
Editorial Note: The median prevalence of current smoking did not change substantially during 2000-2001. However, smoking prevalence varied among the states, DC, Guam, Puerto Rico, and the Virgin Islands. As in 2000, during 2001, Kentucky and Nevada remained among the states with the highest prevalence, and Utah, California, and Puerto Rico remained among all areas with the lowest prevalence.
During 2001, the national health objective for 2010 of <12% of adults smoking cigarettes was achieved only in the Virgin Islands (9.8%). The low prevalence of smoking in the Virgin Islands, Puerto Rico, and Utah might be the result of stronger social and cultural norms against tobacco use compared with other parts of the country.
The findings in this report document that even though current state-specific smoking rates have not declined significantly since 1996, the pattern of smoking has changed. Factors that might have contributed to the shift include increased retail price of cigarettes and smoking bans in public places. Massachusetts and California have reported other changes in smoking patterns. An independent evaluation of the Massachusetts Tobacco Control Program reported a decline in smoking prevalence from 22.6% in 1993 to 20.9% in 1999, with a small but significant decline in the proportion of persons reporting smoking daily (81% in 1993 compared with 79% in 1999). Data collected through the California Tobacco Survey indicated that, along with overall decreases in prevalence of current smoking, the proportion of current smokers who were some day smokers increased significantly from 25.9% in 1992 to 32.1% in 1996 and from 32.1% in 1996 to 36.4% in 1999.
The data in this report are consistent with characteristics of some day smokers observed in the 1997 and 1998 NHIS, except for the higher prevalence of some day smoking among men and the higher prevalence of some day smoking reported by respondents aged >65 years in BRFSS. Although some smokers appear to be reducing their cigarette consumption, results from a recent large cohort study indicate that reduction of daily tobacco consumption by >50% without quitting did not decrease mortality rates from tobacco-related diseases compared with smokers who continued to smoke heavily (>15 cigarettes per day). States are encouraged to implement comprehensive tobacco control programs such as those implemented in California and Massachusetts during the 1990s, which encourage smokers to stop smoking completely.
REF: Centers for Disease Control and Prevention, Morbidity and Mortality Weekly Report, April 11, 2003 / 52(14);303-307
► New Agriculture Fact Book is Now Available
"Agriculture is integral part of our nation’s economic and social fabric," Veneman said. “This new publication provides useful information on a variety of topics including homeland security, conservation, biotechnology, organic foods and energy sources.”
The Agriculture Fact Book 2001-2002 includes general information and statistical data about American food consumption, the agricultural sector and rural America. The book also describes USDA’s wide-ranging programs and services, such as farm programs; exports; rural development, food safety; nutrition; management of land, water, and forests; protecting U.S. borders from pests and diseases; and scientific agricultural research.
As part of USDA’s effort to provide information through the Internet, the Agriculture Fact Book 2001-2002 can be accessed through the web at http://www.usda.gov/factbook. The site includes links and other media that provide further information about agriculture, food, conservation, nutrition, food safety and related issues. Hard copies of the publication are available for sale by the Government Printing Office and can be ordered online at http://bookstore.gpo.gov/.
REF: USDA News Release No. 0101.03
FDA is alerting firms manufacturing mineral mixes and mineral premixes for use in animal feed that minerals that are by-products or co-products of industrial metal production may contain dioxin. Recently, FDA found that some of these by-products or co-products contained high levels of dioxin, and requested that the specific products be recalled. In March 2002, FDA requested a recall of protected minerals and mineral premixes because of high levels of dioxin. In the 2002 case, the source of the dioxins was related to the high temperature process used in making the protected minerals. The Agency believes that in the current case the process used to produce brass resulted in the dioxin contamination of zinc oxide. FDA will be actively checking these and similar products for dioxin.
Dioxins are ubiquitous, low level environmental contaminants. With cumulative exposure, they are potential carcinogens and may cause reproductive or developmental health problems. Environmental sources of dioxin pollution have been markedly reduced over the past decade. The result has been a significant reduction in overall dioxin exposure to the public. Presently, the primary source of human exposure to dioxins is through food.
Earlier this year, FDA’s food and feed surveillance programs detected elevated levels of dioxin in a feed and traced the dioxin to a mineral component of that feed. The implicated zinc oxide and zinc oxide premixes that were used in livestock, aquaculture, and poultry feed contained extremely high levels of dioxin. A recall of these products and feed containing the zinc oxide has been implemented. An additional mineral component (copper oxide) is also being investigated as a possible source of dioxin. Both mineral components currently under investigation are reclamation products from industrial metal production.
FDA's public health objective is to reduce the level of exposure to dioxin in the animal and human foods by finding and stopping sources of added dioxin from entering the food supply. To further reduce public exposure to dioxins, FDA will continue its food and feed surveillance programs, and continue investigating whether other products from industrial metal production that are used as feed ingredients are a source of dioxin.
REF: FDA/CVM Update March 12, 2003
Since 1994, when Congress passed the Animal Medicinal
Drug Use Clarification Act of 1994 (AMDUCA), veterinarians in the U.S.
have enjoyed legitimate extra-label use (ELU) privileges. Veterinarians
can safeguard ELU privileges by following AMDUCA, and by educating clients
(particularly food animal producers) on AMDUCA and prudent drug use principles.
This article outlines key points of AMDUCA in plain language.
The Current List of Drugs Prohibited From Extra-Label
Use (As listed in 21 CFR 530.41). These drugs (both animal and human),
families of drugs, and substances are currently prohibited for extra-label
uses in all food-producing animals, (including horses intended for human
AMDUCA legalized extra-label use of approved animal and human drugs in animals when that use is under the supervision of a veterinarian and in accordance with FDA regulations. AMDUCA provided veterinarians with privileges comparable to those generally enjoyed by physicians. Veterinarians can protect these privileges by complying with AMDUCA, and understanding the permitted and prohibited extra-label drugs and uses (including compounding). For more information on AMDUCA, other regulations and policies, and to request hard copies, please visit the CVM Home Page, http://www.fda.gov/cvm/ default.html, and look under Quick Index. Notices of proposed rulemaking and final rules, such as additions to prohibited drug list, are announced by Federal Register notices and posted on the CVM Home Page, http://www.fda.gov/cvm/default.html and the FDA Dockets Advanced Publication Display website, http://www.accessdata.fda.gov/scripts/oc/ohrms/index.cfm.
REF: FDA Veterinarian, March/April 2003 Vol. XVIII,
Comfrey in Animal Products
The FDA Center for Veterinary Medicine (CVM) supports recent action by the Association of American Feed Control Officials, Inc. (AAFCO) in recommending to State feed control officials that enforcement action be initiated to remove from distribution animal products containing comfrey. AAFCO’s guidance to State feed control officials on March 3, 2003, follows the announcement made at AAFCO’s Annual Meeting in August 2002, that comfrey, determined to be a health and safety concern in animals, is recommended for removal from all animal feeds.
AFCO’s Enforcement Strategy for Marketed Ingredients
Task Force identified comfrey as the target ingredient. This Task Force
based its selection on published scientific information provided
by CVM. Comfrey has been shown to cause liver damage in humans and in
animals. Due to safety concerns, the FDA advised manufacturers on July
6, 2001, that comfrey should not be used in human dietary supplements.
REF: FDA Veterinarian, March/April 2003 Vol. XVIII,