Changes in subjective symptoms and allergy state among medical students exposed to low-level formaldehyde 6 months after completion of a gross anatomy dissection course

Development of a Prediction Model for Subjective Physical Symptoms Induced During Systematic Anatomy Practice Among Medical Students

To prevent unpleasant symptoms in medical students during systematic anatomy practice, we aimed to develop and validate a model that predicts the likelihood of these symptoms occurring during practice based on risk factors prior to the start of practice. A total of 452 medical students enrolled from 2014 to 2018 were surveyed before and during practice, with questions regarding their sex, psychological status, subjective symptoms, and allergies. The sum of the scores concerning three subjective symptoms related to the eyes and three subjective symptoms related to the nose and fatigue were defined as the "eye-score" and "mask-score," respectively, and a total score of 7 or more was considered symptomatic. A prediction model was developed based on a generalized linear mixed model; the outcome variable in the model was symptoms during practice, and the explanatory variables were indoor formaldehyde concentration during practice, sex, and pre-practice status, such as the students' psychological state, eye-score, mask-score, and the presence of allergies. Five-fold cross-validation was used to assess internal validity and the prediction model was applied to 110 medical students enrolled in 2021 to assess external validity. The sensitivity and specificity by five-fold cross-validation were 0.843 and 0.314 for eye symptoms and 0.847 and 0.432 for mask symptoms. In the external validity assessment, the sensitivity and specificity were 0.889 and 0.207 for eye symptoms and 0.879 and 0.532 for mask symptoms. The prediction model developed in this study can be used in future measures aimed at preventing symptoms in students.

Acute Adverse Effects of Formaldehyde Treated Cadaver on New Innovative Medical Students and Anatomy Staff Members in the Dissection Hall at Wollo University, Northeast Ethiopia

INTRODUCTION

Formaldehyde is the most frequently used chemical for the preservation of a cadaver. However, its toxicity in the dissection hall is frequently ignored.

OBJECTIVE

To assess the acute adverse effects of formaldehyde treated cadaver on preclinical new innovative medical students and anatomy staff members in the dissection hall at Wollo University, Ethiopia.

METHODS

This institutional-based cross-sectional study was carried out from January 20 to February 25, 2020. A total of 88 study participants were surveyed at the department of Human Anatomy, Wollo University, Ethiopia. The participants were those who were exposed to formaldehyde vapors during the dissection of a cadaver in the dissection hall. A self-administered questionnaire which contains the clinical symptoms observed after formaldehyde exposure was used to collect data. The data were entered into EpiData version 4.2 and then exported to SPSS Version 21 for analysis. Finally, the data were expressed in texts, tables, and figures.

RESULTS

The study comprised 84 (95.5%) male and 4 (4.5%) female. In this study, the top three most common acute adverse effects of formaldehyde during dissection of a cadaver in the cadaver room were unpleasant smells, Tiredness/dizziness, and watering of eyes (lacrimation), each accounted for 64 (72.7%), 39 (44.3%) and 35 (39.8%), respectively. The other acute adverse effects were running nose with tingling sensation 27 (30.7%) followed by lack of concentration 24 (27.3%) and headache 22 (25%).

CONCLUSION

In dissection hall, preclinical medical students and instructors are at high risk to develop various acute adverse symptoms of formaldehyde. Therefore, a free-aldehyde preservation solution should be assumed to prevent its toxicity.

Levels of formaldehyde vapor released from embalmed cadavers in each dissection stage

Formaldehyde (FA) is an aldehyde used in antiseptics and adhesives. The World Health Organization (WHO) and other institutes have linked FA to sick building syndrome and allergic diseases. Recent studies have reported that cadavers embalmed using formalin and ethanol-based preservative solutions release FA vapor during dissection and that FA vapor may adversely affect students and lecturers in gross anatomy laboratories. However, few details have been reported correlating dissection stage with increased FA vapor release. In this study, we evaluated the vapor level of FA released in each dissection stage. Six cadavers for which consent was given for use in anatomy research and education were examined in this study. Using an active sampling method, FA vapor was collected above the thoracoabdominal region of each dissected cadaver. FA was eluted from each sampler using acetonitrile and analyzed by high-performance liquid chromatography. Our data show that FA levels significantly increase after skin incision and that the vapor level of FA released differs between male and female cadavers. We also found that subcutaneous adipose tissues of the thoracoabdominal-region release FA vapor and that female cadavers release significantly higher levels of FA per kilogram of subcutaneous adipose tissue than do male cadavers. Based on these data, we propose the methods be developed to prevent exposure to FA vapors released from cadavers.

Comparison of subjective symptoms associated with exposure to low levels of formaldehyde between students enrolled and not enrolled in a gross anatomy course

OBJECTIVES

This study aimed to evaluate students' subjective symptoms associated with exposure to low levels of formaldehyde (FA) during a gross anatomy course and to survey how the risk of subjective symptoms was affected by exposure to FA.

METHODS

We conducted three questionnaire surveys of 125 students enrolled in an anatomy course (FA exposure group) and 124 students not enrolled in the course (FA nonexposure group) before, during, and 6 months after the course. The questionnaire included questions inquiring about subjective symptoms, sex, age, and allergies. We analyzed differences in the prevalence of subjective symptoms in distinct survey periods. Furthermore, we analyzed the relationship between the subjective symptoms and exposure to FA after adjusting for allergy, sex, and age using multiple logistic regression analysis.

RESULTS

The prevalence of some of the ocular, nasal, and nonspecific symptoms in the FA exposure group was low before the course, increased during the course and decreased 6 months after the course. A significant positive relationship was observed between exposure to FA and some symptoms after adjusting for allergy, sex, and age.

CONCLUSIONS

We identified some concrete symptoms associated with exposure to FA. We suggest that the exposure to low levels of FA influences students' subjective symptoms.