poster30: consumer acceptance of genetically modified (gm) foods: the case of gm biofortified...

Consumer Acceptance of Genetically Modified (GM)

Foods: The Case of GM Biofortified Cassava in the

Northeast of BrazilCarolina Gonzalez1,4, Nancy Johnson2 and Matin Qaim3

1International Center for Tropical Agriculture– CIAT, 2 International Livestock Research Institute (ILRI), 3 Göttingen University, 4Hoheheim UniversityContacto: [email protected]

MethodologyWe assess acceptance of GM biofortified cassava among consumers in

NE Brazil by estimating their willingness to pay (WTP). Contingent

valuation (CV) and choices modeling (CM) techniques were employed to

estimate consumer WTP.

ResultsUsing the four-point scale data about consumer support of GM cassava,

we estimated a model to explore the factors underlying consumer

perceptions (see Table 1). Consumers who trust the regulatory

authorities are more supportive of the GM technology, while people who

are concerned about GM health risks tend to oppose its introduction.

IntroductionBiofortified staple foods are currently being developed to reduce problems of micronutrient malnutrition among the poor. Research mostly builds on

conventional breeding techniques. Yet there are also species where certain micronutrients are absent, or occur only in very small amounts, so that

use of biotechnology seems more promising. This is the case of cassava and provitamin A. Genetic modification could potentially boost provitamin A

contents, thus more effectively reducing problems of vitamin A deficiency. On the other hand, genetically modified (GM) cassava might raise

consumer concerns about health and environmental risks . The present study examines consumer attitudes towards GM cassava in the Northeast

(NE) of Brazil.

DiscussionWhat does the estimated premium mean in terms of household budget

share? Mean monthly per capita expenditure for cassava is around 3

reais ($1.42), accounting for 1.8% of average household income. A 64%

price premium for GM cassava would increase monthly expenditure to

4.9 reais, or 3% of household income, indicating the strength of

preference/acceptance for more nutritious cassava. Nonetheless, the

idea is not to really sell GM biofortified cassava at a premium. The large

WTP is simply a clear indication of positive acceptance levels and an

expected increase in consumer utility through GM cassava.

AcknowledgementsThe financial support CIAT and the HarvestPlus Challenge Program are gratefully

acknowledged. A especially grateful to Brazilian consumers, who where the key to the

outcome of this study.

ReferencesBateman, I.J., Carson, R.T., Day B., Hanemann, M., Hanley, N. Hett, T., Jones-Lee, M.

Loomes, G., Mourato, S., Özdemiroglu, E., Pearce, D.W, Sugden, R. and Swanson, J.

Economic Valuation with Stated Preference Techniques: A Manual. Edward Elgar,

Cheltenham, 2002.

Based on the CV approach, on average, consumers are willingness to

pay 0.49 reais more (a 64% price premium) for GM cassava than for

traditional cassava without vitamin A.

Using the CM approach we analyzed the trade-offs between different

cassava characteristics and estimated the partial WTP for each

attribute. For the vitamin A alone, the average consumer is willing to

pay premium of 160%. However, a discount is required for the cassava

colour change from white to yellow (-29%), and an additional discount

results from the fact that the cassava is GM (-61%) (see Table 3). The

CM approach generates a mean WTP of 70% over current market

prices.

Conclusions

75% of all respondents in our survey said they would support the

introduction of this new technology.

Based on CV and CM techniques, mean WTP is estimated at 64-70%

above market prices for cassava.

The results also suggest that acceptance would be higher still if

provitamin A were introduced to cassava through conventional

breeding.

CV techniques are often used to analyze individual preferences and elicit

the monetary value of goods that are not yet marketed. CM is a tool to

determine how consumers value different attributes of a certain good

(Bateman, et al., 2002).Variables Coefficient Std. error WTP

Price 1.93*** 0.70

GM status 0.91*** 0.09 -0.47

Vitamin A content -2.36*** 0.15 1.23

Colour (yellow) 0.42*** 0.09 -0.22

Log likelihood -1105.95

Chi-squared 419.53***

Variables Coefficient Std. error

Age 0.02* 0.01

Children <5 0.14 0.25

Education 0.03 0.03

Per capita household income 0.00 0.00

Trust in regulatory authorities 0.55** 0.22

Perceived GM health risks -3.05*** 0.46

Access to mass media 0.48* 0.29


Variables Coefficient Std. error

Cassava price paid (reais/kg) 0.56*** 0.11

Female respondent 0.14** 0.07

Children <5 0.07* 0.04

Per capita household income 0.00 0.00

Cassava consumption (per week) -0.03*** 0.01

Perceived GM health risks -0.29*** 0.08

Trust in regulatory authorities -0.02 0.04

Access to mass media 0.04 0.05

Willingness to eat new products

(reference is high willingness)

a. Average willingness -0.08 0.07

b. Low willingness -0.07 0.08

c. Avoid -0.01 0.08

Preferred way to increase vitamin A

(reference is through GM)

a. Conventional -0.27*** 0.04

b. Indifferent -0.25*** 0.08

Prior knowledge about GM crops 0.09* 0.05


Figure 1. Map of NE Brazil and Pernambuco.

Female respondents and households with small children have a higher

WTP; those who have ethical concerns, or are particularly worried

about health risks of GM crops, have a lower WTP. Household income

levels do not appear to have a significant effect separate from other

socio-economic characteristics (see Table 2).

Table 1. Ordered logit model for explaining consumer support of GM cassava

N=414; *, **, *** statistically significant at 10%, 5% and 1% level, respectively

Table 2. WTP model for GM cassava


Figure 2. “Choice sets” presented to responders and consumers in the NE of Brazil


Table 3. Rank-ordered logit model for GM cassava