I am puzzled

Mercury preservative was removed from house paint in the early 1990s. I posted in my webpage Dental Amalgam and Mercury (http://www.stanford.edu/~bcalhoun/amalgam.htm):

In August 1989, a previously healthy 4-year-old boy in Michigan was diagnosed with acrodynia, a rare manifestation of childhood mercury poisoning. Symptoms and signs included leg cramps; rash; itching; excessive perspiration; rapid heartbeat; intermittent low-grade fevers; irritability, marked personality change; insomnia; headaches; hypertension; swelling; redness and peeling of the hands, feet, and nose; weakness of the pectoral and pelvic girdles; and nerve dysfunction in the lower extremities. A urine mercury level of 65 ug/L was measured on a 24-hour urine collection. Treatment with intensive chelation therapy increased his urine mercury excretion 20-fold. Examination of his mother and two siblings found urine mercury levels greater than or approximately equal to his; his father had elevated, although lower, levels. Parents and siblings were asymptomatic, although electromyographic abnormalities were detected in one sibling.... identified inhalation of mercury-containing vapors from phenylmercuric acetate contained in latex paint as the probable route of mercury exposure for the family; 17 gallons of paint had been applied to the inside of the family's home during the first week of July. Samples of the paint contained 930-955 ppm mercury, the Environmental Protection Agency (EPA) limit for mercury as a preservative in interior paint is 300 ppm. During July, the house was air conditioned, and the windows were not opened...
The preceding quote is an excerpt from an article by Aronow R, Cubbage C, Weiner R, Johnson B, Hesse J & Bedford J, Mercury Exposure from Interior Latex Paint - Michigan, Morbidity and Mortality Weekly Report (MMWR) 39(8):125-126 (1990)

Because of this case a study was done to see if mercury from latex paint can produce toxic levels. The result was described in the New England Journal of Medicine; Oct. 18, 1990; Volume 323:1096-1101, Nr.16 "Mercury Exposure From Interior Latex Paint", by MM Agocs, RA Etzel, RG Parrish, DC Paschal, PR Campagna, DS Cohen, EM Kilbourne, and JL Hesse:

We found that potentially hazardous exposure to mercury had occurred among persons whose homes were painted with a brand of paint containing mercury at concentrations approximately 2 1/2 times the Environmental Protection Agency's recommended limit.

It is puzzling that no one doubts that the mercury in the paint was clearly the cause of toxicity. Mercury apparently caused damage to the family that had lived in that apartment. There was only one complaint, and with little ado and without huge epidemiological studies it was accepted that the mercury was the cause of toxicity. The vehicle to get the mercury into the body was the inhaled mercury-containing air.

Now, when it comes to Thimerosal also a mercury preservative, this substance is apparently not dangerous enough to cause toxicity when it is injected. One might say the reason is that much more mercury was inhaled than was injected. Really? I am puzzled about the duplicity.