Prevalence and Risk Assessment of Aflatoxin in Iowa Corn during a Drought Year

Table 2

Mean aflatoxin contamination (ppb) in corn by crop reporting district (CRD) in 2012 in Iowa. Mean results are reported for each CRD. The % of samples reported that tested above the 20 ppb aflatoxin limit and the % of samples that fell below the limit of detection (LOD).

Crop reporting district (CRD)	Total samples ()	Overall mean (ppb)	value^1	SEM^2	% of samples testing > 20 ppb total aflatoxin	% of samples testing below LOD (limit of detection)
Northwest	48	2.88	0.76	0.28	6.25	20.83
West Central	48	3.90	0.13	0.26	4.17	31.25
Southwest	36	15.13	<0.01	0.25	19.44	58.33
North Central	44	3.17	0.51	0.28	2.27	29.55
Central	48	3.55	0.25	0.26	4.17	33.33
South Central	44	10.86	<0.01	0.23	11.36	63.63
Northeast	44	4.25	0.06	0.26	4.55	38.64
East Central	39	1.78	0.26	0.35	0.00	15.38
Southeast	45	4.60	0.03	0.26	4.44	33.33
Total analyses	396	5.57

¹Main effect of CRD against other CRD in Iowa for AFL contamination levels (ppb). ²Greatest standard error is shown.