The ones I know look about 60, testifying to the stress of the job over the long term.....
I agree with Mike and Tom about the pesticides. There was a GCSAA study, and while many supers had cancer, there was no link established to the pesticides.
I also agree that the trend should improve as the toxicity of pesticides is reduced. The following chart, which is for fungicides, gives an example of why certain concerns are overblown. I forget where I copied this from now, but the point is valid......
RELATIVE TOXICITY OF GOLF COURSE FUNGICIDES
Here is an excerpt of LD50's of commonly used fungicides from Vargas' "Management of Turfgrass Diseases".
Remember that the lower the LD50, the more dangerous it is to rats who ate the human equivalent of probably 10 pounds of these per day.
Caffeine 250 mg/kg (MOST DANGEROUS)
Thiram 780
Aspirin 780
Triademefon 1900
PCNB 2000
Terrazole 2000
Table salt 3320
Chlorothalonil (becoming restricted, totally ridiculous) 3800
Ethyl alcohol 3800
Fosetyl-Al 4600
Iprodione 5000
Anilazine 5000
Vinclozolin 5000
Thiophanate methyl 5800
Mancozeb 8000
Propamocarb 8000
Benomyl 10000
Fenarimol 1000
Chloroneb 11000 Least dangerous
So be sure you wear a hood, gloves and respirator when you have your next cup of coffee, your next aspirin, salt and pepper, or cocktail.