Pulmonary toxicity following exposure to a tile coating product containing alkylsiloxanes. A clinical and toxicological evaluation

Figures & data

Table 1. Selected clinical data on 39 patients exposed to aerosols from a tile-coating product containing alkylsiloxanes.

Parameter	Median (Range)	Reference values
Respiratory symptoms	39/39
Body temperature (°C)	38.1 (37.5–39.4)	36.5–37.5
Heart rate (min^− 1)	95 (61–120)	60–80
O2 saturation (%) (pulse oximetry) (No supplemental oxygen)	97 (76–100)	95–100
Respiratory frequency (min^− 1)	19 (12–40) (N = 33)	12–18
PaO2 (kPa) (with 0–5 L. Oxygen)	11.2 (8.8–21.7) (N = 35)	10–12
PaCO2 (kPa)	5.2 (4.1–5.9) (N = 35)	4.7–6.0
Abnormal plain chest radiograph	7/39

The most unusual findings within 1–12 h after initial exposure to aerosols from a tile-coating product containing alkylsiloxanes.

Fig. 1. Concentration- and time-dependent effects of inhaled SRS product on the tidal volume (a) and respiratory rate (b) in mice (n = 10 per exposure). Each study started with a 15-min pre-exposure baseline period, followed by a 10- to 60-min exposure period. The exposure period is followed by a 30-min recovery period. Generated concentrations are given (colour version of this figure can be found in the online version at www.informahealthcare.com/ctx).

Fig. 2. Langmuir isotherms. Pulmonary surfactant incubated with either SRS product or n-decane (solvent control) is transferred to a KSV mini trough with an area of 243 cm². A reduction of the trough area (compression of the surfactant film) results in an increase in the surface pressure (equal to a reduction of the surface tension). For simplicity and because of loss of surfactant to the subphase during the compression cycles, only the second of three compression isotherms of solvent- or SRS-incubated HL10 are presented.

Fig. 3. Total ion chromatogram showing VOCs emitted after spraying of 83.6 g SRS product at a 2 m² surface of ceramic tiles inside a 20.3 m³ chamber. The major peaks 1 and 2 are assigned as: C₉–C₁₃ hydrocarbons (solvent) and isooctyltrimethoxy silane, respectively. Peak 3 is an unknown organosilane (colour version of this figure can be found in the online version at www.informahealthcare.com/ctx).

Fig. 4. Temporal evolution of particle size distributions (a) and the total particle concentration (n/cm³) over time (b) (colour version of this figure can be found in the online version at www.informahealthcare.com/ctx).

Table 2. Calculated values for alveolar deposited mass for three different exposure times.

Exposure time	15 minutes	60 minutes	150 minutes
Alveolar deposited mass [mg]	1.64	3.11	3.55

Data are from the simulated workplace exposure scenario.