150-50-5 Usage
Description
MERPHOS, an organothiophosphorus compound, was historically utilized as a defoliant in the agriculture industry. It was particularly effective for total defoliation of cotton before machine harvesting, as it induced leaf abscission in a relatively green state. However, its active ingredient is no longer present in any registered pesticide products in the US and the EU, leading the Environmental Protection Agency (EPA) to categorize it as canceled. Despite this, the EU pesticide database still regulates a maximum residue level (MRL) for MERPHOS in foods under Regulation EC 1107/2009.
Uses
Used in Agriculture Industry:
MERPHOS was used as a defoliant for cotton crops, facilitating easier machine harvesting by promoting leaf abscission. It was applied at rates of 1.1–2.2 kg active ingredient per acre and was also effective in inducing leaf drop in other plants, such as roses and hydrangeas.
Additionally, MERPHOS was employed as an organophosphate pesticide in the agriculture industry, with the technical product having a 95% purity level. It was available in formulations containing 720 g of active ingredient per liter or as an emulsifiable concentrate with 6 lb per gallon.
Chemical Properties:
MERPHOS is described as an emulsifiable oil and is characterized as a nearly colorless liquid. It is insoluble in water but soluble in a variety of organic solvents.
Reactivity Profile
Organothiophosphates, such as MERPHOS, are susceptible to formation of highly toxic and flammable phosphine gas in the presence of strong reducing agents such as hydrides. Partial oxidation by oxidizing agents may result in the release of toxic phosphorus oxides.
Hazard
Cholinesterase inhibitor.
Safety Profile
Poison by
intraperitoneal route. Moderately toxic by
ingestion and skin contact. A cholinesterase
inhibitor. Combustible when exposed to
heat or flame. Can react vigorously with
oxidzing materials. When heated to
decomposition it emits highly toxic fumes of
POx and SOx. Used as a defoliant. See also
PARATHION.
Environmental Fate
Merphos is adsorbed strongly to soil and oxidized to
S,S,S-tributyl phosphorotrithioate (DEF). The Koc estimated for
merphos is theoretically 62 000; accordingly, merphos would
be immobile in soil.
In water, merphos will be oxidized to DEF. The fact that
merphos is expected to adsorb strongly to particulate matter in
the water column, apparently did not impede its oxidation.
In the atmosphere, merphos will exist as an aerosol and be
removed by gravitational settling and readily oxidized to DEF.
Vapor-phase merphos will react with photochemically
produced hydroxyl radicals, with an estimated half-life of 4.9 h.
Check Digit Verification of cas no
The CAS Registry Mumber 150-50-5 includes 6 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 3 digits, 1,5 and 0 respectively; the second part has 2 digits, 5 and 0 respectively.
Calculate Digit Verification of CAS Registry Number 150-50:
(5*1)+(4*5)+(3*0)+(2*5)+(1*0)=35
35 % 10 = 5
So 150-50-5 is a valid CAS Registry Number.
InChI:InChI=1/C12H27PS3/c1-4-7-10-14-13(15-11-8-5-2)16-12-9-6-3/h4-12H2,1-3H3
150-50-5Relevant articles and documents
-
Stepashkina,L.V. et al.
, (1972)
-
-
Lippert,Reid
, p. 2370 (1938)
-
Reaction of red phosphorus (P n) with alkanethiolate anions
Trofimov,Gusarova,Verkhoturova,Mikhailenko,Kazantseva,Arbuzova,Kazheva,Aleksandrov,D'yachenko
experimental part, p. 164 - 167 (2010/02/17)
-
Pesticide compositions and method
-
, (2008/06/13)
Toxicant, especially pesticide compositions, having lowered dermal toxicity are provided. The compositions include a lipophilic-pesticide, a nonionic surfactant and a dry inert diluent carrier. Methods for reducing the dermal toxicity of lipophilic toxicants, especially pesticides are provided, as well as methods for controlling insect pests using the disclosed compositions.