Toxicity Class

Toxicity Class

Toxicity Class refers to a classification system for pesticides created by a national or international government-related or -sponsored organization. It addresses the acute toxicity of agents such as soil fumigants, fungicides, herbicides, insecticides, miticides, molluscicides, nematicides, or rodenticides.

General considerations

Assignment to a Toxicity Class is based typically on results of acute toxicity studies such as the determination of LD50 values in animal experiments, notably rodents, via oral, or sometimes inhaled, or external application. The experimental design measures the acute death rate of an agent. The Toxicity Class generally does not address issues of other potential harm of the agent, such as bioaccumulation, issues of carcinogenicity, teratogenicity, or mutagenic effects, or the impact on reproduction.

Regulating agencies may require that packaging of the agent is labeled with a Signal Word, a specific warning label to indicate the level of toxicity to the public.

EPA (United States)

The Environmental Protection Agency knows four Toxicity Classes. Class I to III are required to carry a Signal Word on the label to warn users of the toxicity. Pesticides are regulated by the Federal Insecticide, Fungicide, and Rodenticide Act(FIFRA).

Toxicity Class I

*most toxic;
*requires Signal Word: "Danger-Poison", with skull and crossbones symbol::Possibly followed by::::"Fatal if swallowed", "Poisonous if inhaled", "Extremely hazardous by skin contact--rapidly absorbed through skin", or "Corrosive--causes eye damage and severe skin burns".

Toxicity Class II

*moderate toxic
*Signal Word: "Warning"::possibly followed by::::"Harmful or fatal if swallowed", "Harmful or fatal if absorbed through the skin", "Harmful or fatal if inhaled", or "Causes skin and eye irritation".

Toxicity Class III

*slightly toxic
*Signal Word: Caution ::possibly followed by::::"Harmful if swallowed", "May be harmful if absorbed through the skin", "May be harmful if inhaled", or "May irritate eyes, nose, throat, and skin".

Toxicity Class IV

*practically nontoxic
*no Signal Word required since 2002.

Generally, agents of Class I will kill an adult person at a dose of less than 5 grams (less than a teaspoon), of Class II at 5-30 grams, and of Class III at more than 30 grams

General versus restriced use

Furthermore, the EPA classifies pesticides into those that can be applied by anybody: General Use Pesticides, and those that are restricted, meaning, their application needs to be done by or under the supervision of a certified individual. Application of Restricted Use Pesticides requires that a record of the application is kept.

WHO

The World Health Organization names four toxicity classes as follows:
*Class I – a: extremely hazardous;
*Class I – b: highly hazardous;
*Class II: moderately hazardous;
*Class III: slightly hazardous.

The system is based on LD50 determination in rats, thus an oral solid agent with an LD50 at 5mg or less/kg bodyweight is Class I-a, at 5-50 mg/kg Class I-b, at 50-500 mg/kg Class II, and at more than 500 mg/kg Class III. Values may differ for liquid oral agents and dermal agents.

European Union

There are three toxicity classes in the classification system by the European Union, regulated by Directive 67/548/EEC, namely:
*Class I: very toxic
*Class II: toxic
*Class III: harmful.

Very toxic and toxic substances are marked by the European toxicity symbol.

See also

* Dangerous goods
* Hazard symbol
* Globally Harmonized System

References

* [http://www.who.int/ipcs/publications/pesticides_hazard/en/ WHO Classification document]
* [http://pasture.ecn.purdue.edu/~epados/waste/src/toxrate.htm Toxicity Rating Scale]
* [http://www.ipm.iastate.edu/ipm/hortnews/1994/1-12-1994/undpest.html Reading the label]

External links

* [http://www.agf.gov.bc.ca/pesticides/b_3.htm Canada toxicity symbols]
* [http://grounds-mag.com/mag/grounds_maintenance_protect_yourself/index.html Protect Yourself]
* [http://whatcom.wsu.edu/ag/comhort/nooksack/ipmweb/Pesticideselection.html Pesticide ratings]
* [http://www.mindfully.org/Pesticide/2002/ABCs-Of-Toxicology.htm Critique of model using LD50 values to determine “toxicity”]
* [http://npic.orst.edu/factsheets/signalwords.pdf Signal Words Fact Sheet - National Pesticide Information Center]


Wikimedia Foundation. 2010.

Игры ⚽ Нужно решить контрольную?

Look at other dictionaries:

  • Class III — may refer to: Class III appliance Class III β tubulin Class III NFA firearm Class III PI 3 kinase Class III railroad Pesticide Toxicity Class Class III World Health Organization United States Environmental Protection Agency‎ EU …   Wikipedia

  • Local anesthetic toxicity — While generally safe, local anesthetic agents can be toxic if used in excessive doses or administered improperly. Even when administered properly, patients may still experience unintended reactions to local anesthetics. [Zamanian, R., Toxicity,… …   Wikipedia

  • HAZMAT Class 6 Toxic and Infectious Substances — Poisonous material is a material, other than a gas, known to be so toxic to humans that it presents a health hazard during transportationDivisionsDivision 6.1: Poisonous material is a material, other than a gas, which is known to be so toxic to… …   Wikipedia

  • HAZMAT Class 2 Gases — The HAZMAT Class 2 in United States law includes all gases which are compressed and stored for transportation. Class 2 has three divisions: Flammable (also called combustible ), Non Flammable/Non Poisonous, and Poisonous.DivisionsDivision 2.1:… …   Wikipedia

  • Globally Harmonized System — The Globally Harmonized System of Classification and Labeling of Chemicals or GHS is an internationally agreed upon system set to replace the various different classification and labeling standards used in different countries. The GHS will use… …   Wikipedia

  • 2007 pet food recalls — The 2007 pet food recalls comprise the contamination and wide recall of many brands of cat and dog foods beginning in March 2007, and the ensuing developments involving the human food supply. The recalls in North America, Europe, and South Africa …   Wikipedia

  • Neonicotinoid — Neonicotinoids are a class of insecticides which act on the central nervous system of insects with lower toxicity to mammals. Neonicotinoids are among the most widely used insecticides worldwide, but recently the uses of some members of this… …   Wikipedia

  • Pesticide — A cropduster spraying pesticide on a field Pesticides are substances or mixture of substances intended for preventing, destroying, repelling or mitigating any pest.[1] A pesticide may be a chemical unicycle, biological agent (such as a virus or… …   Wikipedia

  • Glyphosate — Chembox new ImageFile = Glyphosate 2D skeletal.png ImageSize = ImageFile2 = Glyphosate 3D balls.png IUPACName = [(phosphonomethyl)amino] acetic acid OtherNames = Section1 = Chembox Identifiers CASNo = CASRN|1|0|7|1|8|3|6 PubChem = 3496 SMILES =… …   Wikipedia

  • Median lethal dose — This article is about the toxicological term. For the album by Mudvayne, see L.D. 50 (album). For other uses, see LD50 (disambiguation). In toxicology, the median lethal dose, LD50 (abbreviation for “Lethal Dose, 50%”), LC50 (Lethal Concentration …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”