Evaluation of hazardous airborne carbonyls on a university campus in southern China

Figures & data

Figure 1. A map showing the sampling locations on the campus (the representations of numerical location are shown in Table 1).

Table 1. Summary of sampled workplaces and residential areas on the university campus

	Category							Environmental Conditions
Sample Area	No.	Description	Number of Locations	Area (m^3)	Estimated Number of Related Workers/Occupants	Year of Last Decoration	Main Facilities	Temp (°C)	RH (%)	Ventilation System Equipped
Workplace	1	Departmental offices	3	45–64	600	2008	Wooden desks, ledges, bookcase combination, and floorboards; leather chairs	13–22	77–89	Mechanical
	2	Faculty offices	3	13–22	1200	2008	Wooden desks, ledges, bookcase combination, and floorboards; leather armchairs; cotton curtains	14–22	67–91	Mechanical
	3	Supporting staff offices	3	45–62	500	2008	Wooden desks, ledges, bookcase combination, and floorboards; leather chairs	17–22	71–89	Mechanical
	4	Lecture theaters	3	120–176	1200	2010	Wooden benches, chairs, and floorboards	12–23	72–88	Mechanical
	5	Small lecture rooms	3	25–30	1200	2011	Wooden benches, chairs, and floorboards	13–22	73–87	Mechanical
	6	Chemistry laboratory	1	90	200	2003	Wooden benches, chairs, and floorboards; galvanized steel cabinets; fume hood	14–23	67–82	Mechanical
	7	Stationary store	1	120	10	2011	Galvanized steel shelves and cabinets; photocopiers	15–22	68–89	Mechanical
	8	Library	1	1220	80	2002	Wooden desks, chairs, bookshelves, and floorboards; photocopiers	15–23	70–88	Mechanical
	9	Fast food courts	3	200–300	60	2012–2013	Acacia benches and chairs; wooden floorboards; automatic drinking water machines	12–28	65–92	Mechanical
	10	Staff restaurants	3	150–200	30	2006–2008	Acacia tables and chairs; wooden floorboards	13–29	71–95	Mechanical
	11	Commercial bank	1	70–90	45	2005–2008	Galvanized steel desks, shelves, and storage combinations; leather chairs	14–22	72–85	Mechanical
	12	Groceries	3	48–78	30	2002–2005	Galvanized steel shelves and cabinets; refrigerators	13–23	67–86	Mechanical
Residential Unit	13	Faculty apartments	3	90–110	2400	2011	Wooden dining tables and chairs, television bench, cabinets, decorations, and floorboards; cotton/polyester cover sofa; cotton curtains	13–24	75–84	Mechanical
	14	Student dormitories	3	35–42	1700	2010	Wooden beds, wardrobes, desks, chairs, and floorboards; cotton curtains	13–28	65–93	Natural
	15	Safe guard hostels	3	12–16	30	2006	Wooden beds, wardrobes, cabinets, and floorboards	13–31	63–95	Natural

Table 2. Minimum detection limits (MDL) for the target carbonyls

Anonym	Carbonyl	CAS#	MW	Class	MDL (ppbv) ^a
C1	Formaldehyde	50-00-0	30	Aliphatic monocarbonyl	0.12
C2	Acetaldehyde	75-07-0	44	Aliphatic monocarbonyl	0.13
ACE	Acetone	67-64-1	58	Aliphatic monocarbonyl	0.27
nC3	Propionaldehyde	123-38-6	58	Aliphatic monocarbonyl	0.08
MEK	Methyl ethyl ketone	78-93-3	72	Aliphatic monocarbonyl	0.07
iC4	iso-Butyraldehyde ^b	78-84-2	72	Aliphatic monocarbonyl	0.17
nC4	n-Butyraldehyde ^b	123-72-8	72	Aliphatic monocarbonyl	0.17
Benz	Benzaldehyde	100-52-7	106	Aromatic monocarbonyl	0.11
iC5	iso-Valeraldehyde	590-86-3	86	Aliphatic monocarbonyl	0.13
nC5	n-Valeraldehyde	110-62-3	86	Aliphatic monocarbonyl	0.16
o-tol	o-Tolualdehyde	529-20-4	120	Aromatic monocarbonyl	0.18
m-tol	m-Tolualdehyde	620-23-5	120	Aromatic monocarbonyl	0.19
p-tol	p-Tolualdehyde	104-87-0	120	Aromatic monocarbonyl	0.21
C6	Hexaldehyde	66-25-1	100	Aliphatic monocarbonyl	0.17
C7	Heptaldehyde	111-71-7	114	Aliphatic monocarbonyl	0.21
C8	Octaldehyde	124-13-0	128	Aliphatic monocarbonyl	0.22
C9	Nonaldehyde	124-19-6	142	Aliphatic monocarbonyl	0.20
C10	Decaldehyde	112-31-2	156	Aliphatic monocarbonyl	0.23
2,5-DB	2,5-Dimethylbenzaldehyde	5779-94-2	134	Aromatic monocarbonyl	0.24
gly	Glyoxal	107-22-2	58	Dicarbonyl	0.23
mgly	Methylglyoxal	78-98-8	72	Dicarbonyl	0.19

Notes: ^aThe MDL is the minimum detection limit of a carbonyl on a cartridge. The MDL expressed as ppb_v is calculated using a sampled air volume of 0.168 m³ (at a flow rate of 0.7 L/min for 240 min). ^biso-Butyraldehyde and n-butyraldehyde were co-eluted in the HPLC analysis.

Table 3. Average carbonyl concentrations (ppb_v) in the indoor environments on the campus

		Carbonyl Concentration (ppbv)^a
Category	Number of Samples	C1	C2	ACE	nC3	MEK	i+nC4	benz	iC5	nC5	o-tol	m-tol	p-tol	C6	C7	C8	C9	C10	2,5-DB	gly	mgly	Total
Workplaces
Departmental offices	60	57.6 ± 14.4	4.12 ± 2.45	9.32 ± 3.19	2.12 ± 1.41	0.64 ± 0.34	0.96 ± 0.44	0.60 ± 0.22	0.88 ± 0.19	0.84 ± 0.36	bd ^b	bd	bd	9.56 ± 2.43	1.24 ± 0.43	0.64 ± 0.27	bd	bd	0.48 ± 0.16	0.84 ± 0.35	0.88 ± 0.54	90.7 ± 24.3
Faculty offices	80	39.8 ± 9.12	2.90 ± 1.34	5.16 ± 1.46	1.24 ± 0.61	0.56 ± 0.25	0.66 ± 0.26	0.42 ± 0.37	0.38 ± 0.11	0.50 ± 0.23	bd	bd	bd	6.02 ± 1.56	0.84 ± 0.42	0.38 ± 0.16	bd	bd	bd	0.48 ± 0.22	0.66 ± 0.17	60.0 ± 20.4
Supporting staff offices	60	25.2 ± 7.78	3.34 ± 1.20	4.04 ± 1.52	0.88 ± 0.47	0.58 ± 0.22	0.62 ± 0.25	0.36 ± 0.17	0.30 ± 0.12	0.40 ± 0.16	bd	bd	bd	4.38 ± 1.33	0.54 ± 0.20	bd	bd	bd	bd	0.64 ± 0.18	0.76 ± 0.22	42.0 ± 12.3
Lecture theaters	60	8.60 ± 3.82	1.03 ± 0.66	1.33 ± 0.76	0.26 ± 0.18	0.17 ± 0.06	0.18 ± 0.08	0.09 ± 0.06	0.31 ± 0.15	0.33 ± 0.21	bd	bd	bd	1.99 ± 0.86	0.18 ± 0.13	bd	bd	bd	bd	0.24 ± 0.08	0.28 ± 0.15	15.0 ± 5.66
Small lecture rooms	80	13.4 ± 5.26	1.37 ± 0.76	1.45 ± 0.71	0.37 ± 0.23	0.22 ± 0.11	0.27 ± 0.14	0.13 ± 0.07	0.28 ± 0.24	0.45 ± 0.25	bd	bd	bd	1.87 ± 1.54	0.12 ± 0.08	bd	bd	bd	bd	0.22 ± 0.06	0.36 ± 0.16	20.5 ± 8.77
Chemistry laboratory	20	67.2 ± 24.9	45.6 ± 17.2	154.4 ± 39.6	16.7 ± 4.32	12.4 ± 3.65	15.8 ± 4.16	3.98 ± 1.86	1.76 ± 0.82	4.34 ± 1.33	bd	0.78 ± 0.45	0.56 ± 0.23	1.13 ± 0.52	0.87 ± 0.32	0.62 ± 0.27	bd	bd	0.76 ± 0.41	1.33 ± 0.44	1.68 ± 0.54	330 ± 71.5
Stationary Store	20	16.9 ± 5.98	16.1 ± 5.23	15.3 ± 4.76	11.5 ± 3.33	8.88 ± 2.93	3.34 ± 1.87	1.52 ± 0.76	1.04 ± 0.54	1.52 ± 0.63	bd	bd	bd	0.46 ± 0.32	0.36 ± 0.31	bd	bd	bd	bd	0.26 ± 0.22	0.28 ± 0.17	77.5 ± 26.5
Library	20	10.6 ± 4.55	7.56 ± 2.33	6.25 ± 2.13	4.38 ± 2.21	3.46 ± 1.14	1.53 ± 0.67	0.68 ± 0.33	0.49 ± 0.21	0.81 ± 0.19	bd	bd	bd	1.87 ± 0.54	bd	bd	bd	bd	bd	0.12 ± 0.07	0.18 ± 0.08	37.9 ± 9.11
Fast food counts	60	107 ± 26.4	56.4 ± 14.3	23.5 ± 8.76	14.5 ± 5.12	10.6 ± 4.22	5.43 ± 1.65	2.67 ± 0.66	1.98 ± 1.03	2.76 ± 0.87	bd	0.37 ± 0.22	0.15 ± 0.08	0.76 ± 0.43	5.43 ± 1.65	9.15 ± 3.10	29.8 ± 8.66	4.35 ± 2.33	2.63 ± 1.44	0.76 ± 0.42	0.91 ± 0.54	277 ± 54.2
Staff restaurants	60	87.3 ± 34.4	26.5 ± 8.87	17.9 ± 6.22	17.6 ± 6.85	6.30 ± 2.42	10.4 ± 3.67	1.20 ± 0.76	3.51 ± 1.39	1.60 ± 0.48	bd	bd	bd	1.22 ± 0.76	3.76 ± 2.05	8.54 ± 5.12	18.7 ± 13.4	4.12 ± 2.51	bd	0.87 ± 0.62	0.54 ± 0.37	210 ± 56.4
Commercial banks	60	4.67 ± 2.29	1.76 ± 1.02	1.89 ± 0.76	0.67 ± 0.41	0.25 ± 0.16	0.37 ± 0.22	0.16 ± 0.09	0.16 ± 0.08	0.24 ± 0.13	bd	bd	bd	bd	bd	bd	bd	bd	bd	0.11 ± 0.09	0.15 ± 0.08	10.4 ± 4.87
Groceries	60	12.5 ± 4.76	4.44 ± 2.07	3.26 ± 1.86	1.96 ± 1.03	0.54 ± 0.43	0.46 ± 0.34	0.30 ± 0.22	0.44 ± 0.13	0.68 ± 0.37	bd	bd	bd	0.82 ± 0.37	0.92 ± 0.41	0.46 ± 0.24	bd	bd	bd	0.50 ± 0.27	0.82 ± 0.33	28.1 ± 8.78
Residential units
Staff apartment	60	26.5 ± 7.23	6.34 ± 3.21	10.4 ± 4.35	1.33 ± 0.76	0.78 ± 0.35	1.23 ± 0.67	0.87 ± 0.52	0.52 ± 0.31	0.78 ± 0.44	bd	0.12 ± 0.11	bd	4.34 ± 1.67	0.52 ± 0.24	0.98 ± 0.47	5.44 ± 2.43	1.27 ± 0.54	0.13 ± 0.07	0.52 ± 0.36	0.78 ± 0.35	62.9 ± 19.4
Student dormitory	80	18.1 ± 5.12	2.35 ± 0.98	3.24 ± 1.35	0.87 ± 0.43	0.43 ± 0.28	0.86 ± 0.54	0.26 ± 0.19	0.57 ± 0.31	0.66 ± 0.41	bd	bd	bd	1.34 ± 0.87	0.23 ± 0.13	bd	bd	bd	bd	0.23 ± 0.14	0.36 ± 0.25	29.5 ± 8.76
Safe guard hostel	60	30.8 ± 7.65	13.5 ± 5.80	5.38 ± 3.56	2.47 ± 0.98	4.34 ± 2.11	2.82 ± 0.87	2.34 ± 0.76	0.97 ± 0.73	2.43 ± 0.86	bd	0.44 ± 0.24	0.34 ± 0.23	2.36 ± 0.91	1.12 ± 0.78	0.30 ± 0.22	bd	bd	0.42 ± 0.24	1.34 ± 0.76	1.96 ± 1.13	73.3 ± 20.3

Notes: ^aAnonyms as defined in Table 2. ^bbd = below minimum detection limit.

Figure 2. Carbonyl molar compositions in the 15 categories of workplaces and residential units.

Figure 3. Carbonyl molar concentrations (ppb_v) in off- and on-duty periods.

Figure 4. Variations in carbonyl composition profiles in the comparison studies.

Table 4. Chronic daily intake (CDI) and lifetime cancer hazard risk (R) for formaldehyde and acetaldehyde in the workplaces and residential units

							Formaldehyde					Acetaldehyde
		IR (m^3/hr)						Male		Female			Male		Female
Description	Duty Mode	Male	Female	ET (hr/day)	EF (day/yr)	ED (yr)	Conc. (μg/m^3)	CDI ^a (× 10^−4)	R ^b (× 10^−4)	CDI (× 10^−4)	R (× 10^−4)	Conc. (μg/m^3)	CDI (× 10^−4)	R (× 10^−4)	CDI (× 10^−4)	R (× 10^−4)
Workplace
Departmental offices	Light	0.8	0.5	8	5 × 52	40	70.7	24.0	1.09	16.8	0.76	7.41	2.52	0.0194	1.76	0.0136
Faculty offices	Light	0.8	0.5	8	5 × 52	40	48.9	16.6	0.76	11.6	0.53	5.22	1.77	0.0137	1.24	0.00954
Supporting staff offices	Light	0.8	0.5	8	5 × 52	40	31.0	10.5	0.48	7.35	0.33	6.01	2.04	0.0157	1.43	0.0110
Lecture theaters	Light	0.8	0.5	8	5 × 52	40	10.6	3.59	0.16	2.51	0.11	1.85	0.63	0.00084	0.00076	0.00059
Small lecture rooms	Light	0.8	0.5	8	5 × 52	40	16.5	5.59	0.25	3.91	0.18	2.47	0.84	0.00112	0.00101	0.00078
Chemistry laboratory	Light	0.8	0.5	8	5 × 52	40	82.5	28.0	1.28	19.6	0.89	82.1	27.9	0.149	0.135	0.104
Stationary store	Light	0.8	0.5	8	5 × 52	40	20.8	7.05	0.32	4.93	0.22	28.9	9.83	0.0757	0.0687	0.0529
Library	Light	0.8	0.5	8	5 × 52	40	13.0	4.42	0.20	3.09	0.14	13.6	4.62	0.0356	0.0323	0.0249
Fast food courts	Moderate	2.5	1.6	8	5 × 52	40	131.9	140.1	6.37	100.0	4.56	101.5	107.8	0.830	0.771	0.594
Staff restaurants	Moderate	2.5	1.6	8	5 × 52	40	107.2	113.9	5.18	81.5	3.71	47.7	50.6	0.390	0.362	0.279
Commercial banks	Light	0.8	0.5	8	5 × 52	40	5.74	1.95	0.089	1.36	0.062	3.17	1.08	0.00829	0.00752	0.0058
Groceries	Moderate	2.5	1.6	8	5 × 52	40	15.3	16.3	0.74	11.6	0.53	7.99	8.48	0.0653	0.0607	0.0467
Residential unit
Faculty apartment	Resting	0.7	0.3	24	7 × 52	40	32.5	40.6	1.85	19.5	0.89	11.4	14.3	0.457	0.284	0.219
Student dormitory	Resting	0.7	0.3	24	7 × 52	40	22.2	27.8	1.26	13.3	0.61	4.23	5.28	0.0117	0.0730	0.00562
Safe guard hostel	Resting	0.7	0.3	24	7 × 52	40	37.8	47.2	2.15	22.6	1.03	24.3	30.3	0.23	0.606	0.466

Notes: ^aChronic daily intake in mg kg⁻¹ day^{−1. b}Lifetime cancer hazard risk based on the following assumptions: average body weights of 70 kg for male and 60 kg for female, and a lifetime of 69 yr for male and 72 yr for female.