The standard is designed to protect the health and safety of employees for up to a 10-hour work shift, 40-hour workweek, over a working lifetime. Compliance with all sections of the standard should therefore prevent adverse effects of carbaryl on the health and safety of employees. The recommended standard Is measurable by techniques that are valid, reproducible, and available to industry and government agencies. Sufficient technology exists to permit compliance with the recommended standard. The criteria and standard will be subject to review and revision as necessary. The criteria and the recommended standard apply to any manufacturing, formulating, or applying operation in which carbaryl is produced, packaged, processed, mixed, blended, handled, or used, or where employees are otherwise potentially exposed. "Carbaryl" is the generic name for the 1naphthyl ester of N-methylcarbamic acid or 1-naphthyl N-methylcarbamate. "Action level" is defined as one-half the recommended time-weighted average (TWA) environmental exposure limit for carbaryl. "Occupational exposure to carbaryl" is defined as exposure to airborne carbaryl at concentrations greater than the action level. Exposure to carbaryl at concentrations less than or equal to the action level shall not require adherence to the recommended standard, except for Sections 3, 4(a,b), and 7(b). If employees are potentially exposed to other chemicals, such as pesticide vehicles, diluents, or emulsifiers or other pesticides, provisions of any (7) At the time of the preplacement examination, it Is recommended that a preexposure baseline erythrocyte cholinesterase activity be determined. (8) A judgment of the worker's physical ability to use negative or positive pressure respirators. (b) Emergency first-aid services shall be established, under the direction of the responsible physician, to provide care to any worker acutely intoxicated by carbaryl (See Appendix III). (c) Appropriate medical services and surveillance shall be provided to any worker with adverse health effects from exposure to carbaryl. (d) Pertinent medical records shall be maintained for all workers occupationally exposed to carbaryl for at least 5 years after termination of employment. These records shall be available to the designated medical representatives of the Secretary of Health, Education, and Welfare, of the Secretary of Labor, of the employee or former employee, and of the employer. Section 3 -Labeling and Posting (a) Labeling Containers of carbaryl shall bear the following label in addition to, or in combination with, labels required by other statutes, regulations, or ordinances: 4 CARBARYL CAUTION! HARMFUL IF INHALED, SWALLOWED, OR LEFT ON THE SKIN NO SMOKING Avoid breathing dust or spray mist. Avoid contact with eyes, skin, and clothing. Wash hands and face thoroughly before eating. Wear long-sleeved work clothes. Shower or bathe and change into clean clothing after work. First Aid: On skin contact with carbary1, wash with soap and water. On eye contact, flush eyes with copious amounts of water. If inhaled or swallowed, consult a physician. Note to Physician: Carbaryl is a moderate, reversible Cholinesterase inhibitor. Atropine sulfate is the antidote. Do not use pralidoxime chloride (2-PAM). (b) Posting The following sign shall be posted in a readily visible location at or near entrances to manufacturing and formulating areas containing carbaryl, and at other areas in which there is a risk of exposure: CARBARYL CAUTION! HARMFUL IF INHALED, SWALLOWED, OR LEFT ON THE SKIN NO SMOKING Avoid breathing dust or spray mist. Avoid contact with eyes, skin, and clothing. Wash hands and face thoroughly before eating. Wear long-sleeved work clothes. Shower or bathe and change into clean clothing after work. First Aid: On skin contact with carbaryl, wash with soap and water. On eye contact, flush eyes with copious amounts of water. If inhaled or swallowed, consult a physician.#
applicable standards for such chemicals shall also be followed. (2) Any employee applying carbaryl by aircraft shall be provided with, and required to carry in the aircraft, a respirator as specified in Table 1-1.
(3) Employees working as flaggers shall wear appropriate respirators as specified in Table 1-1 when exposure to an airborne carbaryl concentration above that specified in Section 1 is likely to occur.

# Respirators may also be worn during the time necessary to

# III. BIOLOGIC EFFECTS OF EXPOSURE
The carbamate insecticides, one of which is carbaryl, and the organophosphate insecticides as well, exert their insecticidal action by Inhibiting cholinesterase enzymes.  This inhibition is the primary mechanism by which these insecticides cause toxicity in mammals. The           When this absorption value of carbaryl (5.6 mg/8 hours) was compared to the total potential dermal and respiratory exposure value (600 mg/8 hours) for the formulating-plant workers, it was suggested that absorption from dermal contact with carbaryl dust was probably not very complete. The authors concluded that dermal absorption of carbaryl from dry formulations in formulating plants may be only a small fraction of the total potential calculated exposure. probably makes the degree of inhibition by carbaryl at any given time elusive. The enzyme activity when analyzed in the sample tends to be higher than was the actual case when the blood sample was obtained, and thus the degree of inhibition may be interpreted as less than actually occurred.   Degenerative changes in the testes, including edema of interstitial tissue and destruction of germinal epithelium, were noted in carbaryl-treated male rats. In females, the estrus cycle was prolonged at the 14 and 70 mg/kg doses. In a three-generation reproduction study on gerbils given carbaryl in the diet (2,000, 4,000, 6,000, and 10,000 ppm), Collins et al  reported that no litters were produced at 10,000 ppm in the F3b generation, and that there was a decrease in fertility, pup viability, litter size, and survival of pups (to day 4 and to weaning) which appeared sporadically at all dose levels.
In a similar three-generation reproduction study, Collins et al  reported that doses of 5,000 and 10,000 ppm carbaryl in the diet reduced survival of offspring, viability of the pups, and litter size in rats from the first generation on. At 2,000 ppm, only body weight gain of the parents and weanling weight were affected. In contrast, Weil et al  did not see any effect when carbaryl was administered by dietary inclusion to rats in a dose range of 7-100 mg/kg. An increased duration of the gestation period was the only effect seen at 200 mg/kg in the diet.
Administration of carbary1 by gastric intubation to rats in a dose range of The carcinogenic potential of carbaryl has been investigated in mice.
 Male mice received 10 mg carbaryl subcutaneously once weekly during their 3rd to 8th months of life. by measurement of urinary 1-naphthol levels. To provide a safety factor for protection against systemic effects, a Threshold Limit Value of 5.0 mg/cu m was recommended. While available data to derive a safe limit are insufficient, there is no significant evidence indicating that the limit should be changed. In the absence of these needed data, it is proposed that the present workplace environmental limit of 5.0 mg carbaryl/cu m as a TWA concentration be continued.
Available data do not indicate that exposure of workers at this concentration will result in intoxication, and some data suggest that this limit offers a good margin of safety. However, pertinent investigations, including epidemiologic studies of workers exposed to carbary1, are needed to validate this recommended limit or, if appropriate, to provide a basis for a better limit.
Sampling and analysis methods were reviewed in Chapter IV. Airborne particulate carbaryl should be collected on a glass-fiber membrane filter mounted with a backup pad in a two-piece closed-face cassette. This sampling method, chosen because it is the best now available, has been shown to provide the required degree of collection efficiency for airborne particulate carbaryl. A colorimetric method was selected for analysis of carbaryl because it is reliable, sensitive, and simple to carry out. The selected method is not entirely specific for carbaryl analysis and several compounds including 1-naphthol can interfere with the precision of the method if they are present in the air sample to be analyzed.

# VI. WORK PRACTICES
Occupational exposures to carbaryl may occur among people engaged in the manufacture, formulation, or application of the insecticide.
Potentially exposed applicators include agricultural workers, spray pilots, and exterminators.
 Even though absorption of pesticides by the oral and respiratory routes may be more rapid and more complete than by the percutaneous route, the amount of absorption by ingestion and inhalation is probably too small a fraction of the total potential exposure to be considered the main factor in most cases of intoxication of workers in the field.
 Studies also showed that considerably more insecticide was deposited on exposed skin surfaces than that reaching the respiratory tract.

# FIGURE XIII-1 CALIBRATION SETUP FOR PERSONAL SAMPLING PUMP WITH FILTER CASSETTE D E P A R T M E N T OF HEALTH, EDUCATION. A N D W E L F A R E P U B L IC H E A L T H SER VIC E C E N T E R F O R D IS E A S E C O N T R O L N A T I O N A L IN S T IT U T E FO R O C C U P A T IO N A L S A FE TY A N D H E A L T H R O B E R T A. T A F T L A B O R
The head and neck should be protected from contact with carbaryl.
 Therefore, some type of protective headgear, such as waterproof rainhats and washable safety hardhats and caps, should be worn. Waterproof or water-repellant parkas also may be used to protect the head and neck at the same time. Materials impervious to all carbaryl formulations should be identified for use in protective clothing.

# Wills JH:
The measurement and significance of changes in the Cholinesterase activities of erythrocytes and plasma in man and animals.  MATERIAL SAFETY DATA SHEET

# IO N R A T E (B U T Y L A C E T A T E M I A P P E A R A N C E