Concentrations and Diversity of Microbes from Four Local Bioaerosol Emission Sources in Finland

Figures & data

Table 1. Median, minimum, and maximum concentrations of fungal and bacterial groups from different types of emission sources, determined with qPCR and expressed as cells/m³

Waste Center
	Composting Windrows			Dumping Ground			Population Center
	Median	Min	Max	Median	Min	Max	Median	Min	Max
Clado	157008	112258	211774	83027	37427	524328	39854	19163	78545
PenAsp	5860	1208	42252	85	35	90	81	68	125
Afumi	1135	48	3256	ud	ud	4	ud	ud	3
Strepto	31	23	82	1	0.3	4	1	1	1
Sewage Treatment Plant
	Plant Area			Population Center 50 m			Population Center 200 m
	Median	Min	Max	Median	Min	Max	Median	Min	Max
Clado	21707	13247	30631	4466	2166	23755	4134	1324	18806
PenAsp	472	245	884	209	81	408	163	65	258
Gram+	2565	1201	3830	120	82	173	90	49	169
Gram−	1743	836	2706	385	248	692	298	245	449
Strepto	12	6	17	5	1	11	4	1	7
Farming Environment
	Next to the Cowshed			50 m from the Cowshed			150 m from the Cowshed
	Median	Min	Max	Median	Min	Max	Median	Min	Max
Clado J	16379	3961	36016	60996	6195	236330	34556	2585	110463
Clado N	ud	ud	464	141	ud	323	245	ud	278
PenAsp J	66	23	192	54	48	170	66	23	212
PenAsp N	38	17	67	34	16	176	115	35	1936
Gram+ J	7013	1136	26689	17441	3140	89667	43557	6395	182958
Gram+ N	880	326	1100	729	241	1294	236	ud	432
Gram− J	44266	15373	611453	67061	15248	2054333	296183	28541	715752
Gram− N	1711	1183	2210	2533	873	3295	2096	746	3332
Strepto J	7	3	139	10	2	258	19	ud	190
Strepto N	6	3	8	3	ud	3	7	2	130
Manure Spreading
	10 m			50 m			200 m
	Median	Min	Max	Median	Min	Max	Median	Min	Max
Clado B	16023	689	31358	36543	677	72409	15409	7296	23523
Clado A	67392	48053	312325	46308	39178	478314	99963	93912	178872
PenAsp B	70	28	112	84	13	155	280	73	487
PenAsp A	33	1	60	25	8	73	37	10	84
Gram+ B	348	179	517	309	128	489	227	159	294
Gram+ A	1487	672	4595	465	88	2030	1141	392	1323
Gram− B	772	ud	1543	997	ud	1993	552	ud	1104
Gram− A	1028	765	5790	1233	ud	7257	2176	664	2458
Strepto B	12	1	23	12	ud	24	7	3	10
Strepto A	10	2	16	8	1	31	17	0.5	33
Notes: ud = under detection limit; J = sampling campaign in June; N = sampling campaign in November; B = before spreading; A = after spreading.

Figure 1. Microbial concentrations within and in the vicinity of the waste centre as determined by qPCR analyses. The columns represent geometric mean concentrations and 95% confidence intervals of three measurements at each site. The sampling sites were next to the composting windrows, on the dumping ground and in the nearby population center. Notes: Clado = Cladosporium spp.; Cherb = Cladosporium herbarum; Cclad1 = Cladosporium cladosporioides; PenAsp = Penicillium/Aspergillus/Paecilomyces variotii; Afumi = Aspergillus fumigatus/Neosartorya fischeri; Anigr = Aspergillus niger/awamori/foetidus/phoenicis; Pbrev = Penicillium brevicompactum/stoloniferum; Pchry = Penicillium chrysogenum; Pvarb2 = Penicillium variabile; Apull = Aureobasidium pullulans; Eamst = Eurotium amstelodami/chevalieri/herbariorum/rubrum/repens; Enigr = Epicoccum nigrum; Wsebi = Wallemia sebi; Strepto = Streptomyces spp.

Figure 2. Total concentration of viable bacteria and fungi in three sampling points downwind from the emission source. The columns represent the geometric mean of 2–10 measurements with an Andersen six-stage impactor. Sampling point 1 (black column) is next to the emission source and 2 and 3 as increasing distances. In the waste center area, sampling point 1 is in next to the composting windrows, sampling point 2 in perimeter of the dumping ground, and sampling point 3 in a population center. *P < 0.05; **P < 0.01.

Figure 3. Microbial concentrations in the sewage treatment plant area and in the nearby population center determined with qPCR. Geometric mean concentrations and 95% confidence intervals of 6 samples at each site are presented. For qPCR assay abbreviations, see Figure 1. *P < 0.05; **P < 0.01.

Figure 4. Geometric mean concentrations and 95% confidence intervals of fungal species/groups, Gram-positive and -negative bacteria and the bacterium Streptomyces spp. in the farming environment next to the cowshed and in two locations at different distances on the prevailing downwinds from the cowshed, determined with qPCR (n = 6 at each site in June and n = 3 at each site in November). J = June; N = November. For qPCR assay abbreviations, see Figure 1. *P < 0.05; **P < 0.01.

Figure 5. Concentrations of fungi and bacteria before, during, and 1–5 days after cattle manure spreading in three prevailing downwind distances from the spreading area, determined with qPCR. The four columns in a group represent the four sampling times; from left to right: before, 0–1 days after, 1–3 days after, and 3–5 days after manure spreading. For qPCR assay abbreviations, see Figure 1.

Figure 6. Daily variation in the concentrations of Cladosporium spp. (Clado), Penicillium/Aspergillus/P. variotii group (PenAsp), and Gram-positive and -negative bacteria measured with qPCR. Different symbols in the vertical lines illustrate the concentrations measured on each individual day. The numbers (1–3) in the x-axis represent the three distances from the emission source. In the farming environment, the concentrations measured in November are marked with a cross (×).