Formaldehyde exposure and atmospheric biomonitoring with lichen Cladonia verticillaris in an anatomy laboratory.

Formaldehyde is one of the most toxic contaminants of indoor environments and very common in the anatomy laboratory. In this work, we investigated the level of formaldehyde exposure to staff and students who attended an anatomy lab and in nearby environments in the same university building. We also performed atmospheric biomonitoring of the sites with the lichen Cladonia verticillaris. Quantification samplings were performed over four weeks, on 7 days with and 7 days without practical classes, totaling 70 samples. The samples were collected in five different locations, three points inside the laboratory and two points outside the laboratory, representing nearby and susceptible environments to contamination. The results showed CHOH concentrations from 0.20-3.76 ppmv for days with practical courses and 0.17-3.06 ppmv for days without practical classes. Although the laboratory was more contaminated than the surrounding environments, the concentration of formaldehyde in these areas is not negligible, showing a dispersion of formaldehyde from the laboratory. Potential dose (PD) and cancer risk (CR) were calculated for an individual exposed to the same levels analyzed for 8 h daily and 30 years of work. The study on C. verticillaris lasted 90 days and evaluated the variation of chlorophyll and pheophytin (photosynthetic pigments). The results showed a significant difference in the production of chlorophylls a and b and total chlorophyll when compared to control, and there was also a progressive increase of the total pheophytin/total chlorophyll ratio. The results also showed the correlation between the increase in chlorophylls and the studied environments with less ventilation since these places provided greater accumulation of formaldehyde in the long run. Thus, measurable evidence was obtained of biological disorders in a living organism caused by exposure to formaldehyde.