Indicators for early identification of re-emerging mycotoxins

Figures & data

Fig. 1 Concept for the food chain's host environment (adapted from Noteborn et al. [3] and Noteborn [4]).

Fig. 2 Number of interviews in which the experts classified the particular indicators in the top five of most important indicators.

Table 1 Most frequently mentioned indicators (>25% of the interviews) for early identification of re-emerging mycotoxins in wheat, maize and nuts, with percentage of interviews (n = 13), as well as total score of each indicator per commodity.

Influential sector/Indicator	Percentage interviews^a	Total score per indicator and per crop (with rank)^b^,^c
		Wheat	Maize	Nuts
Food chain
Traceability	38	9	9	12
Mixing	31	7	7	6
Transport conditions	62	12	12 (4)	15 (4)
Storage conditions	77	20 (3)	17 (1)	20 (1)
Agriculture
Scale of production	46	10	11	13
Tillage practice	54	16 (4)	10	2
Crop variety	46	14	8	2
Genetically modified crops	31	7	7	1
Crop rotation	46	13	7	0
Irrigation and drainage	31	7	7	9
Use of pesticides	31	7	8	6
Harvest conditions	31	10	11	10
Environment and energy
Humidity/drought	77	23 (1)	17 (1)	19 (2)
Temperature	77	22 (2)	16 (3)	18 (3)
Industry and trade
Global trade	38	8	6	6
Changes in trade flows	31	5	4	4
Other markets (e.g., biofuel)	31	3	2	0
Government and politics
Regulations with respect to mycotoxins	54	14	11	12
Communication and information
Information flows	46	6	6	10
Education within food production chain	46	12	10	13
Population and social conditions
Changes in eating pattern	69	10	11	8

a Percentages >50 are printed bold.

b Based on 10 interviews for wheat, eight interviews for maize and nine interviews for nuts.

c The ranking of the four indicators with the highest score is in parentheses.

Table 2 The 10 main indicators for identification of re-emerging mycotoxins in wheat, maize and nuts, as well as total score and relative ranking (based on total score) per indicator for wheat, as judged by individual experts (during workshop).

Indicator	Total score^a	Ranking
Humidity (relative)/drought	128	1
Temperature	97	2
Crop rotation	93	3
Tillage practice	83	4.5
Storage conditions	83	4.5
Crop variety	80	6
Transport conditions	66	7
Global trade	37	8
Regulations with respect to mycotoxins	33	9
Changes in eating patterns	14	10

a Maximum score is 130.

Table 3 The seven most important indicators for identification of re-emerging mycotoxins in wheat, together with their description.

Indicator	Description
1. Relative humidity	Relative humidity (RH) during crop growth. Ideally, RH is expressed as leaf wetness (moisture on the surface of the leaf). Precipitation (in combination with temperature) and irrigation normally are used as alternative. For RH, three time windows during crop growth are important: the period around/at flowering, two weeks before harvest, and delayed harvest
2. Temperature	Temperature during crop growth. Temperature is only relevant in case humidity is conditioning (thus, in combination with humidity). Consequently, the same three windows as defined for relative humidity are also important for temperature
3. Crop rotation	The crop that is grown on the field prior to wheat and/or in previous year(s). Growing maize before wheat or wheat before wheat increases the possibility of the occurrence of mycotoxins. Especially maize before wheat is a potential risk factor
4. Crop variety	Susceptibility/resistance of the used variety to mycotoxin-producing fungi. Resistance levels are variable (not absolute), and not always clearly defined and also not stable over time. Recommended varieties vary among countries
5. Tillage practice	Tillage practice used before the crop is sown. Tillage practices may include: no tillage, medium tillage, deep-tillage (and burning). Tillage practices vary among countries. In the Netherlands, burning is prohibited and deep-ploughing is not used because of erosion.
6. Drying of the kernel	In the EU, a moisture content <15% of the grain is recommended during storage, and therefore proper drying before storage is often necessary
7. Storage (and transport) conditions	In case grain moisture content is kept at or below 15% mycotoxins will not be formed. Moisture contents above 15% pose a risk for the formation of mycotoxins, and also favour the growth of other fungi. Presence of pests and/or insects as well as high fluctuations in outside temperature could lead to a local increase in moisture content. The moisture content of the grain at the start of transportation or storage is therefore important but can be controlled by proper drying after harvest. Kernel damage can be relevant when moisture content increases