Farm family exposure to glyphosate Monsanto U Mn School of Public Health Rollins School of Public Health Exponent Corp. Published in Environmental Health Perspectives

Glyphosate characteristics Low acute oral LD 50 (> 5,000 mg/kg) Not considered to cause mutagens, cancers, no effect on reproductive system or development Low vapor pressure – low inhalation potential Dermal penetration < 2% of dose placed on skin Overall low potential for harm to applicators

Study Purpose Identify real-world pesticide exposure and factors before, during, and after application Glyphosate – 2 nd in pounds applied in US agriculture – US EPA 2002

Participants Certified pesticide applicators – South Carolina & Minnesota Farmer, spouse, 1+ child 4 to 18 years old Live on farm Farm at least 10 acres within 1 mi of residence Make at least 1 glyphosate application / yr

Answer questions and allow observation Collect all urine for 5 consecutive days – day before, application day, 3 consecutive days after 48 families – 78 children Field observer documented weather, application practices, family activities Participants

Characteristics 48 families – 25 MN 23 SC Average age – farmer 45, spouse 42 Used pesticides for 23.9 years 15% cigarette smokers Few spouses personally mixed pesticides

Practices – survey responses 29% applied glyphosate within 7 days of study 22% never wore protective gloves 27% changed gloves 1 to 4 times per season 96% of spouses had not mix pesticides within 1 week of study

Practices 60% used enclosed cab tractors 33% treated 10 to 44 ac; 33% - 45 to 145 ac; 33% to 439ac 25% - 1 to 2 loads; 31% - 3 loads; 25% 4 to 6 loads; 19% 7 to 12 loads Most applied Roundup Ultra

Spray day observations 71% wore rubber gloves - mixing /loading/ application 31% had skin contact w/ glyphosate 15% spills during mixing and /or loading 27% repaired their equipment at some time during the application

Results – Applicator

Detectable glyphosate in urine Level ranged from <1 ppb to 332 ppb Some sprayed > 100 acres – no detection in urine 60% of application day samples positive 27% positive 3 days after

96% used rubber gloves 1.4 ppb in urine 43 % used rubber gloves 7.9 ppb in urine 3.2 ppb mean for all farmers – application day

Glyphosate in urine (ppb) Yes No Wore gloves when mixing Closed cab Mixing loading spill Application spill Observed skin contact Equipment repair7.22.3

Glyphosate in urine (ppb) Acres treated No. of loads

Factors associated with INCREASE in urinary glyphosate when gloves NOT used More Acres treated Mixing / loading operations Observed spills Equipment repairs

Results – 78 children 9 (11%) had detectable levels of glyphosate - all from South Carolina 8 of 26 (31%) present during mixing or application had detectable levels Highest conc (29 ppb) in teenage boy most active in assisting with mixing and application - father had highest urine conc (233) - had spills, spent long periods repairing boom & smoked during repairs

Results – 48 spouses None participated in applications 2 (4%) had detectable levels of glyphosate – highest 3 ppb 8 in immediate area of mixing and loading- none had detectable levels 40 (83%) washed applicators clothes during study – 2 (5%) had detectable glyphosate levels (1 ppb)

Glyphosate exposure Maximum farmer dose was mg/kg Average farmer dose was mg/kg EPA lowest no effect level set at 175 mg/kg/d Estimated daily oral exposure for life with no harmful effect – 2 mg/kg/d

Limits of study Only one application evaluated per family All were tractor boom sprayer applications Participation in study may have affected behavior of applicators

Some lessons Use of rubber gloves when mixing, loading, and applying glyphosate was associated with greatly reduced urinary concentrations of glyphosate Little evidence of glyphosate exposure to family members not participating in or around exposures Increased loading, mixing, and repairs increases potential for exposure What would you add?

Reminders Glyphosate is not as likely to be absorbed through the skin or enter through the lungs as other pesticides used on the farm Glyphosate metabolism in the body may be very different than that for other pesticides This study points out factors that affect exposure – the effects will vary with other products