Pesticides Lec22 Revised SG

Lecture 22-23 revised for Exam 3

Pesticides

– economically justified poisons which affect target and non target species

– economically justified poisons which affect target and non target species

Circle of Poison Pesticides

pesticides such as DDT, that are banned in the US but used abroad on food crops which are then imported back into the US, resulting in exposure to the US population

Pesticide Resistance

propensity for pest targeted by pesticides to develop adaptive strategies to survive pesticide exposure, rendering many pesticides ineffective for safe use in the environment

No-Till Farming

replaces tillage with a tractor with increased reliance on herbicide use to eradicate weeds

Herbicides

pesticides used to eradicate plant pests such as weeds

Insecticides

pesticides used to eradicate insect pests

Fungicides  

pesticides  used to eradicate fungal pests 

Nematicides

pesticides used to eradicate nematode pests 

Rodenticides

pesticides used to eradicate rodent pests 

Biocides or Disinfectants

pesticides used to eradicate bacterial, viral or protozoan pests 

Pesticide Tolerance

safe levels of pesticides that can be used or tolerated within the environment 

Average Daily Intake( ADI

safe level of a pesticides that a nontarget species can bioaccumulate without harm

No Observable Effects Level (NOEL)

Concentration of a pesticide that is used as “Safe Level” in pesticide risk assessments  

-Insect Growth regulators-

3^rd generation insecticides that mimic insect hormones that control development and growth and are invertebrate endocrine disruptors (e.g. Methoprene)

Microbial Insecticides

3^rd generation insecticides derived from bacterial toxins which target specific insect species without harm to non-target species (e.g. BTI

$32 Billions 

value of global pesticide sales in 2000 which have steadily increased from $2.5- $3.0 billion in 1950  

$78.7 Billion

value of global pesticides sold in 2021 

32%

the proportion of total global pesticide manufactured products that are used in China each year, more than any country.

5.24 PAI/acr

the average pesticide use in pounds per acre, on crops in China 

18%

the proportion of total global pesticide manufactured products that are used in the USA each year, the 2^nd largest global use.  

1.02 PAI/Acre

the average pesticide use in pounds per acre, on crops in the USA 

SC Golf Courses

account for $2.7 billion in sales, over 33,000 jobs and $834 million in personal income and use 80 PAi/acre the highest use in SC.  

Atrazine

herbicide which is the most widely used pesticides in the US which is reported to be an Endocrine Disruptor and may affect frogs (demasculinization in males & increased hermaphrodism)

Texas, Maryland and Ohio

states with the highest atrazine exposure to the public in drinking water (> 8 million people/state). 

Chlordane and Chlorpyrifos

termitacides found primarily in coastal areas adjoining urban development.  

DDT - para-, para-dichloro Diphenyltrichloroethane

used world-wide for mosquito control and was banned under the Stockholm Convention. 

Hexachlorocyclohexane (HCH)

Most heavily used insecticide in the world in the 1970s-80s and is the most abundant pesticide in arctic air & water. 

Endosulfan

an organochlorine insecticide that caused more coastal fish kills than all other pesticides combined. 

EDCs

Endocrine Disrupting Chemicals that mimic male (testosterone) and female (estrogen) hormones and may alter growth, reproduction and development. 

 

168 –

the number of currently registered pesticides which pose a potential cancer risk to humans 

21

The number of high volume pesticides that pose a potential cancer risk to humans 

-Global considerations - Circle of Poison Pesticides =

pesticides banned in the US (e.g. DDT) which show up in our food supply due to the globalization of the world’s food supply.

Global Pesticide Use

(1) Flavin et al. (2002), global pesticide sales have steadily increased from $2.5- $3.0 billion in 1950 to approximately $32 billion dollars in 2000. (2)Kaufman and Franz (2000) notes that the U.S. used the most pesticides of any country accounting for 30% of global pesticide use. (3) Western Europe and Asia also had high pesticide usage rates of 25% and 16% respectively, followed by Latin American at 13% and Japan at 12% of global pesticide use. (4) Eastern Europe (2%) and Africa (2%) had the lowest use of pesticides  globally (Kaufman and Franz, 2000).

Pesticide Use in the US

(1) In the US there are 50 manufacturers, but 14 firms account for 85% of all pesticides sold in the US.  (2) In 1983-2000 nearly 0.95 billion PAI were sold in the US with an estimated value of >$6 - $9 billion in the US.

Pesticide Use Statistics for the US

Agricultural Use – 77%; Industry and Government – 16%; & Home and Garden – 7%

Pesticide Use in the US

includes >960 (1,154) AI Pesticides Registered in US including (1)240 Herbicides; (2) 225 Insecticides;  (3) 170 Fungicides & Nematicides; (4) 35 Rodenticides; and (5) 210 Disinfectants. These AI pesticides are sold in >25,000 formulations. This results in in the use of 4.4 lbs. of pesticide is used per person/year in the US. 

Pesticide Regulations in the US - Historical Overview includes

(1) 1906 – Pure Food Law; (2)1910 – Federal Insecticide Act; (3) 1938 – Amendments to the Federal Insecticide Act;  (4) 1947 – Federal Insecticide,  Fungicide, and Rodenticide Act (FIFRA); (5) 1954 – Miller Amendment to the Food, Drug & Cosmetic Act (1906, 1938); (6) 1958 – Food Additives Amendment to the Food, Drug & Cosmetic Act (Dulaney Clause); (7) 1959 – Amendments to  FIFRA; (8) 1964 – Amendments to  FIFRA; (9) 1970 – FDA passes authority to EPA; (10) 1972 – The Federal Environmental Pesticide Control Act (FEPCA=FIFRA amended); (11) 1975, 1978, 1980, 1981 – Amendments to FIFRA amended; (12) 1993 – Food Quality Protection Act 

The Scotts Miracle-Gro Company

a producer of pesticides for commercial and consumer lawn and garden uses, was sentenced today in federal district court in Columbus, Ohio, to pay a $4 million fine and perform community service for eleven criminal violations of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), which governs the manufacture, distribution, and sale of pesticides. Scotts pleaded guilty in February 2012 to illegally applying insecticides to its wild bird food products that are toxic to birds, falsifying pesticide registration documents, distributing pesticides with misleading and unapproved labels, and distributing unregistered pesticides. Scotts admitted that it applied the pesticides Actellic 5E and Storcide II to its bird food products even though EPA had prohibited this use.This is the largest criminal penalty under FIFRA to date. In a separate civil agreement with the U.S. Environmental Protection Agency (EPA), Scotts agreed to pay more than $6 million in penalties and spend $2 million on environmental projects to resolves additional civil pesticide violations. The violations include distributing or selling unregistered, canceled, or misbranded pesticides, including products with inadequate warnings or cautions. This is the largest civil settlement under FIFRA to date. 

Classes of Pesticides

(1)  Insecticides – pesticides that control insect pests includes (1) 1st Generation – Organochlorines = DDT (Legacy Chemicals – High KOW); (2) 2nd Generation – Organophosphates – Malathion, Clorpyrifos and Carbamates – Sevin, Aldicarb; and (3) 3rd Generation - Pyrethroids – Fenvalerate as well as Insect Growth Regulators (IGRs) - Methoprene, Dimilin and Microbials – BTI (Bacillus thuringensis israeliensis), BTK, BS; (2) Herbicides – pesticides used to control plant pests (most widely used class of pesticides) including  Atrazine (Most widely used pesticide in the US), Round-Up, & 2,4 D/2,4,5 T (Agent Orange) ; (3) Fungicides – pesticides used to treat fungal pests including Pentachloraphenol (PCPs), Folpet, and Captan (Thaliamide Like Chemicals – birth defects);  (4) Biocides – pesticides used to control bacterial, viral & protozoan pests including Chlorine, Ozone, BrCl2; and (5) Rodentacides – pesticides used to control rodent pests including Warfarin (4 Hydroxy Coumarin). 

Golf is a very big business in South Carolina

- 350-plus golf courses statewide in coastal areas; Golf generates more income than any other entertainment or recreation activity in the state. In 2007, golf accounted for more than $2.7 billion in sales, over 33,000 jobs and $834 million in personal income- There are 462 golf courses in SC,  which translates into approximately 34,000 acres of golf course turf in SC, or approximately 53 square miles. 15% of Horry County is Golf Courses. Pesticide Use on Golf Courses = >80PAI/acre = Highest pesticide use rate in the state. More than 5,920 PAI of Pesticide/ Golf Course  X 462 Golf Courses in SC = 2,735, 046 PAI Pesticides used State-Wide in SC

-SC Crops with high pesticide Use - #10 Agricultural Commodity - Peaches**

$75.2Million (35 PAI pesticide/acre) and Tomatoes ($30 Million) (18 PAI/acre) = two highest agricultural pesticide use in SC. 

Atrazine

adversely affects Spartina alterniflora (salt marsh grass) by reducing biomass production and causing chlorosis in the plants, resulting in detection of plant stress by hyperspectral imagery using satellites. It is an endocrine disruptor that may in part impact frogs and has been implicated in human illness, as it affects the thyroid gland.

FIFRA and FIFRA AMENDED 1970-1993 VERSUSFOOD QUALITY PROTECTION ACT (FQPA)

1994 - (1) FIFRA 1967-1993 - # of new pesticides registered /year = 3-35, averaging 13/year versus FQPA After 1994 - # of new pesticides registered /year = 20-31, averaging 27/year (207% increase) ; (2)  FIFRA 1967-1993 - # of new insecticides registered /year = 0-8,averaging 4/year  versus FQPA 1994-Present -- # of new insecticides registered /year = 11-16,averaging 14/year (350% increase). Bottom line is under FQPA the # of new pesticides being introduced each year is increasing and none of these new compounds are being monitored in traditional monitoring programs = termed   Contemporary Use Pesticides (CUPs).

Pesticide Mortality Rate in Humans

0.65 deaths/million (Between 200-300 deaths/year in the US) and 100 nonfatal poisonings/fatal poisoning >20,000-50,000 non-fatal poisonings/year in the US)

Pesticide Occupational Risks

Skin Disorders (Chloracne) most common occupational illness; Disease Rate 8.5illnesses/1000 farm hands versus 2.5 illnesses/1000 manufacturing.

SC Pesticide Poisoning  Statistics (Hospital Admissions)

1971-1973 (39 cases/yr) with Organochlorine insecticides versus 1979-1982 (79 cases/year) with organophosphate insecticides; 1992-96 -16-31 cases/year with most cases in non-occupational exposures in the general public (children and container issues). Significant rise in intentional cases of poisoning (Suicides).

Gloves

Gloves were very effective at reducing pesticide exposure - (1) 2,4-D was measured in the urine of farmers who applied the herbicide by either boom spray or hand spray. Farmers who wore chemical-resistant gloves had about 70% less 2,4-D in their urine on average than those who did not wear gloves. (2) Captan   - was measured from the hands of orchard farmers who had completed spraying the fungicide by airblast or hand spray. Farmers who wore chemical-resistant gloves had about 80% less captan on their hands on average than farmers who did not wear gloves. CONCLUSIONS:  Gloves significantly reduce pesticide exposure 

-Pesticides and Hypothyroidism

Dr. Whitney Goldner of the University of Nebraska Medical Center, Agriculture & Health Study researchers examined the possible link between thyroid disease and pesticide use among 16,529 female spouses of licensed pesticide applicators. RESULTS: (1) The team found that women who used the organochlorine insecticides lindane or chlordane were 20 to 30% more likely to have an underactive thyroid. (2) Women using the herbicide paraquat was associated with an 80% increase in risk of a hypo-active thyroid.(3) Women who used the fungicides benomyl or maneb/mancozeb were more than twice as likely to have an underactive thyroid.

USGS: National Monitoring Results US

(1) p,p DDE – found at 99% of site ; (2) biphenyl- 94%; (3)transnonachlor-77%*; (4)cis-chlordane -64*; (5) pentachloroanisole -64%; (6) trans-chlordane – 61%; (7) diedrin -60%*; (8) Alpha-BHC -55%*; (9) 1,2,3 trichlorobenzene – 53%; and (10) Hexachlorobenzene -46%  of sites*  [* = Legacy Pesticides (High KOW) = Persistent Organic Pollutants (POPs)] 

Pesticides and Cancer Risk

66 epidemiology studies have been done with what are considered high risk pesticides. High risk cancers include Lymphohematopoietic (e.g. non Hodkins Lymphoma, Mylenomas and Leukemia); Genitourinary (e.g. Prostrate, Bladder, Kidney and Testis); and Gastrointestinal (e.g. Colorectal, colon and Pancreas); and Childhood Cancers e.g. (Acute Lymphocytic Leukemia)

Pesticides in Breast Milk

Pesticide Levels in Breast Milk in US include  (1) Dieldrin – 164.2μg/kg; (2) Heptachlor Epoxide – 91.40 μg/kg #; (3) Oxychlordane – 95.80 μg/kg # (# - Potential Carcinogens). Levels of PCBs have declined in Breast Milk since the 1980’s but levels of other contaminants (Flame Retardents have increased). Pesticides in Breast Milk – primarily pesticides with a high KOWs.

Risk Assessment for Pesticides in Breast Milk

(1) DDT - 5 μg/kg/day [ADI= Safe Level for Human Consumption (Adults)] - Mean Concentrations in Breast Milk -13.80 μg/kg/day (2-3 times ADI) and Max. Conc  = 38.4 μg/kg/day  (5-6 times ADI)); (2) Dieldrin - 0.10[ADI= Safe Level for Human Consumption (Adults)] - Mean Concentrations in Breast Milk -0.92 μg/kg/day (9-10 times ADI) and Max. Conc  = 73.8 μg/kg/day  (>700 times ADI); and (3)Heptachlor epoxide - 0.50[ADI= Safe Level for Human Consumption (Adults)] - Mean Concentrations in Breast Milk -0.52 μg/kg/day (Mean Conc.  At the ADI) and Max. Conc. = 12.3 μg/kg/day  (>24 times ADI)). CONCLUSISONS: POPs with high KOWs accumulate in breast milk and may pose risks.

Pesticides in Breast Millk Epidemiology Studies

Dr. Michael Rogan – NIEHS has conducted a long-term study and has followed Long Term Cohort of Children in NC who were either bottle fed or breast fed for > 30 years. Conclusions of Study (Children in mid-late 30’s now):  (1)No increased rate of death or increased rates of cancer (Rates in Breast Fed = Rates in Bottle Fed); (2) Breast fed children missed fewer days of schools (Positive Benefits of Breast Feeding); and (3) Breast fed children scored higher on Standardized Tests and had higher rates of academic achievement(Positive Benefits of Breast Feeding). Bottom line is through > 30 years post exposure breast fed children do not have increased risk of cancer and there were clear benefits gleamed from breast feeding.