Chemical pesticides agro chemicals

What are Pesticides ?
Pesticides are chemicals used to control pests. The term ‘pesticide’ includes insecticides, herbicides, fungicides, algaecides and fumigants.

Thrust Areas.

  • Analysis of technical grade pesticides and formulations
  • Residual pesticide analysis
  • Establishing of MRL values for pesticides
  • Certification of organic farming products
  • Shelf life studies as per CIB guidelines
  • Analytical toxicology of agrochemicals


Analysis of Technical Grade Pesticides and Formulations
What are Technical Grade Pesticides ?
Technical grade pesticides are chemical compounds consisting of 85 percent or more of the active chemical constituent and the rest are impurities produced during chemical synthesis.

What are Pesticide Formulations ?
Pesticide formulation consists of one or more active pesticide ingredients plus other ingredients which have no pesticidal action i.e. inert ingredients. Inert ingredients generally include, fillers, talc, petroleum distillate, solvents, wetting agents, extenders, emulsifiers, adjuvants etc. 

Types of Formulations
Depending upon the intended use of pesticides there are different types of formulations

 

Solids
Dust or powders Granules, Pellets, Tablets Particulates or Baits 
Dry flowables
Wettable powders
Ear tag/Vapour strips 
Seed treatment WDGs  		Liquids
Suspensions Concentrate (Flowables)
Solutions Emulsifiable concentrates
Gels Aerosol 
Ultralow volume concentrates 
Microemulsions Suspoemulsions 		Gases
Fumigants sold as liquids or solids
  • Factors Responsible for different types of formulations
  • Chemistry of the active ingredient
  • Toxicology of active ingredient
  • Effectivity of the product against the pest
  • Effectivity of the product on the plant, animal or surface
  • Effectivity of the product on the environment
  • Method of application and equipment used
  • Rate of application


Why is the analysis required for the technical grade pesticides and the pesticide formulations

  • To ensure the percentage purity of active ingredient in both technical gradesand formulations as per the labelled claim by the manufacturers
  • To ensure the suitability of the pesticide formulation for its intended use.
  • To ensure safe and judicious use of pesticides
  • To ensure the shelf life of active ingredient.


What are the quality norms and protocols followed for analysis

  1. Analysis is done as per both National and International standards with following major protocols:
    Bureau of Indian Standard specifications.
    CIPAC
    WHO specifications
    FAO specifications
    AOAC specifications
  2. In-house validated method and procedure
  3. Party’s specification

Test Parameters
In order to ensure the right quality of the pesticide, besides testing for the active ingredient, it is also necessary to test other parameters give in the list below :

Type of Materials/ Formulations Test parameters
Technical grade pesticides Moisture content, melting point, setting point, isomeric ratio, relative density, acidity / alkalinity
Water dispersible powder Sieving test, suspensibility, wettability, acidity / alkalinity
Dusting powder Sieving test for particle size, bulk density after compacting, acidity / alkalinity
Granules Encapsulation i.e. Attrition test and water run-off test, sieving test for granule size, sieving test for dust, moisture, acidity/alkalinity.
Emulsifiable concentrates, Soluble liquids Emulsion stability, cold test, acidity/alkalinity, flash point.

Role of  CHEMRTL
CHEMRTL  plays an important role in analyzing and certifying the pesticides both technical grade and formulations for their safe use. CHEMRTL  has the facilities to carry all the above mentioned tests to ascertain the conformity various national or international specifications.
Analysis of Residual Pesticides

Major Categories of Residual Pesticides
Organochlorines
– Solids
– Poor water solubility
– Highly lipophilic
– Persistent and toxic
– Accumute in animal fat accumulatesOrganophosphorus
– Liquids
– Appreciable water solubility
– Rapidly metabolized
– Not very persistent
– Highly toxicPyrethroids
– Solids, used for health care
– Partially water soluble
– Rapidly degraded
– Not persistent
– Highly toxic

Organochlorines and organophosphorus pesticides are of major concern as they accumulate in animal body fat either as such or in the form of metabolites.
What are the causes of Residual Pesticides ?

Persistent nature of pesticidesUnawareness amongst farmersContamination of water and soilDirect application of pesticides during storageImproper timings of pesticide application

Why is it important to analyse residual pesticides ?
It is important to analyze residual pesticides because 

Residual pesticides is one of the important factors to prove that the food is safe for consumptionMandatory requirements by regulatory authorities for all exports of food and food productsMandatory requirement of PFA for domestic market

Role of  CHEMRTL
CHEMRTL  has the state of the art equipment and technology for :

Residual analysis of all pesticides in ppb to sub ppb levels as per the EU, WHO, USFDA and PFA norms as applicable in
Food grains
Fruits and vegetables
Meat and meat products
Water and Beverages		Honey
Milk and milk products
Spices
Processed foods
Method development and validation for determination of residual pesticides in complex matricesData generation for studying residual effects of new pesticide molecules for registration of the product with CIB

Establishing Maximum Residual Limits (MRL) values for pesticides
What is MRL value ?
MRL is the maximum concentration for a possible residue on crop or food commodity resulting from the use of pesticides and is expressed in mg/kg of the commodity.

What is the status of MRL values for various pesticides registered in India ?

Number of pesticides registered in India 
Pesticides for which MRLs have been fixed under PFA act, 1954 
Pesticides for which MRLs yet to be fixed 
Pesticides for which registration data has been submitted but MRLs not fixed 
Pesticides for which no data is available		– 181
– 71
– 32
– 24
– 8
For certain banned pesticides – Still no data is available

Why is it necessary to generate data to establish the MRL values ?

For India to build its own food standards based on scientific and health criteria under the Indian conditions keeping in view the international norms.Revision of standards to be an ongoing processR & D on daily intake of various food items to decide the intake rate of pesticidesRegular agreement of actual exposure of consumers to pesticide residues with respect to the diet basket.

Role of  CHEMRTL
CHEMRTL  has all the sophisticated equipment and technology and can help to fix the MRL values for various pesticides in different food and farm products.

Packaging/Shelf Life or Stability Enhancement of Shelf Life Studies
What is Shelf life
Shelf life refers to the period from initial preperation and packaging during which the technical grade pesticides or the formulation remains within its physical, chemical and toxicological specifications at the specified storage condition. It should meet the appropriate standards of identity, quality and purity of active ingredient.

What are the factors affecting Pesticide Stability

Environmental factors such as:TemperatureLightAirOxygenMoistureCarbon dioxideOther ingredients in the formulationsLeachings from containers

How are the stability tests conducted ?

Stability testing of pesticides is based upon well designed studies to determine the retention of product integrity (i.e. percent active ingredient, physical characteristics, chemical parameters and efficacy) as a function of time. Studies are done at accelerated conditions as well as controlled room temperature conditions.The product samples are analysed at various intervals by validated analytical methods.

Why is it important to conduct shelf life / stability studies ?
It is a mandatory requirement by CIB that the manufacturers should submit the data for shelf life studies at the time of getting their product registered.

Role of  CHEMRTL
CHEMRTL  has the complete arrangement to take up the studies for shelf life or enhancement of shelf life as per the CIB guidelines.

According to CIB guidelines :

Pesticides or their formulations are stored under three different agro-climatic conditions of the countryProperties are determined at fixed intervals of time over a prolonged period to study the deterioration pattern

Certification of Organic Farming
What is organic farming ?
Organic farming refers to agricultural methods

Without any use of chemical pesticides, fungicides or weedicidesWithout any use of chemical fertilizers (eg urea, potassium sulfate, superphosphate etc.)

What are the principles involved in organic farming ?
The principles involved in organic farming are :

All seeds and plant material should be certified as organic i.e. seeds and plants should not be chemically treated with any synthetic pesticides.Accumulation of heavy metals in the soil should be minimalManure should be certified as organicWater used for irrigation should be free from pesticides or heavy metal contamination.The livestock should be fed 100% organically grown feed of good qualityAll relevant measures should be taken to minimize pesticide contamination from outside and within the farm by wind drift, drainage and irrigation.No use of fumigants or chemicals during storage

What does organic certification involve ?
Organic certification involves

Farm certificationProduct certification

Role of CHEMRTL
CHEMRTL  plays an important role in certification of organic farming by carrying out analysis of samples of :

Product of organic produceCrop during the stages of its growthSoil used for organic farmingFeed for the live stockWater used for irrigation

For the following contaminants

Pesticides, herbicides or fungicidesHeavy metalsMinerals and fertilizers

Analytical Toxicology of Agrochemicals
CHEMRTL  provides comprehensive range of toxicity studies as per the national and international norms for different pesticides and their formulations by carrying out – 

Acute / Sub acute toxicity studies by following routes :

OralDermalInhalationSkin and eye irritation

Studies are conducted on mice, rabbits, guinea pigs, fish, bird, honey bee etc.

Long term toxicity studiesMutagenecity studiesReproductive studies on ratsCarcinogenecity studies on rats and mice

Development of pesticide formulations

CHEMRTL provides the customer based requirements for development of different type of pesticides formulations whether aqueous based or oil based. CHEMRTL  also provides the services for development of surface-active agents for the pesticide formulations. It includes the development of new generation environmental friendly formulations.