Work-related respiratory symptoms and lung function among solderers in the electronics industry: a meta-analysis

Abstract

Objective Research on the respiratory effect of exposure to solder fumes in electronics workers has been conducted since the 1970s, but has yielded inconsistent results. The aim of this meta-analysis was to clarify the potential association. Methods Effect sizes with corresponding 95% confidence intervals (CIs) for odds of respiratory symptoms related to soldering and spirometric parameters of solderers were extracted from seven studies and pooled to generate summary estimates and standardized mean differences in lung function measures between exposed persons and controls. Results Soldering was positively associated with wheeze after controlling for smoking (meta-odds ratio: 2.60, 95% CI: 1.46, 4.63) and with statistically significant reductions in forced expiratory volume in 1 s (FEV1) (-0.88%, 95% CI: -1.51, -0.26), forced vital capacity (FVC) (-0.64%, 95% CI: -1.18, -0.10), and FEV1/FVC (-0.35%, 95% CI: -0.65, -0.05). However, lung function parameters of solderers were within normal ranges [pooled mean FEV1: 97.85 Conclusions Soldering may be a risk factor for wheeze, but may not be associated with a clinically significant impairment of lung function among electronics workers.

Main Incompatibilities of Soldering Process in Automotive Industry

“…The melting point of the eutectic Sn-Ag solder (221 °C) is higher than that of the eutectic Sn-Pb solder (183 °C). In connection with this, several-stage soldering technology was used, which consists of the SMD process and wave soldering [4][5].…”

“…It is believed that the reduction and even elimination of the incompatibilities will positively affect the quality of the manufactured components and reduce downtime in the production process [2][3]. It is expected that the introduction of the proposed changes will make a significant contribution to the reduction of the quality costs of the production [4][5]. Main defects in point-to-point soldering process are connected with wrong parameters of the process.…”