Ministry hits back at NCU cassava study

Below is a response by the Ministry
of Agriculture to a recent article on cassava published in The Gleaner of April 13, 2009. In this article, The Gleaner quoted from a study done by a graduate student and his supervisor from the College of Natural and Applied Sciences at the Northern Caribbean University (NCU).

The NCU study involved the collection of 10 samples of cassava from four parishes where the researchers apparently found hydrocyanic acid content (HCN) levels above what is acceptable globally.

The ministry has been very deliberate in its response and has sought to meet with the relevant persons at NCU to discuss the study before publicly responding. Individuals from the Ministry of Agriculture visited the university and met with the dean of natural and applied sciences and his staff. Although we were given an abstract of the research, we were denied access to the full study.

This is unfortunate and disappointing because we would have liked to learn more about the research methodology used and the findings, given that the ministry has tested five byproducts of cassava namely bammy, cassava flour, pancake mix and farina at the Mona Institute of Applied Sciences over the last eight months and found levels of HCN below the limits set by the International Food Standards Organisation.

Concerns about test efficacy

Just to note, the ministry's research staff, in the meeting with the dean, raised concerns about the efficacy of the test that was applied and the determination of the sample size. The use of 'picrate acid paper strips' used in the study is categorised as a 'qualitative', not a 'quantitative', test to determine HCN levels by many food scientists.

In the ministry's opinion, and in the absence of a full copy of the research paper, we have determined that the paper-strip test should have been followed by a laboratory test called 'hydrolysis' which is a true quantitative test as this measures HCN acid level as minute as 5 micro grams, i.e. 1/5000th of a gram.

Given that we were not privy to the full study, there are some important questions that need to be raised.

1. The impact of the small sample size used in this study on the findings.

2. Can the authors eliminate the possibility that the cassava they received was not properly processed?

3. Given the statement, as reported in the newspaper, that the samples consisted of 'undried' cassava flour, do Jamaicans consume 'undried' cassava flour?

Globally, over 500 million people rely on cassava as their main source of calories. These include countries in Africa, Asia, and Latin America. Research done in Africa has indicated health issues with the long-term consumption of cassava. However, such health issues have been associated primarily with persons who are already malnourished and are especially problematic in areas experiencing severe famine.

Research has also indicated that these health issues are associated with shortcuts taken in processing the product. Proper processing involves drying, soaking in water, rinsing or baking, which effectively reduces the cyanide content in cassava.

Bureau of Standards Registration

It is mandatory for any company that is producing food for human consumption to be registered by the Bureau of Standards Jamaica (BSJ). Registration involves an assessment of the manufacturers' facilities and a microbiological and chemical analysis of the product(s).

If all the requirements of the BSJ are met, the company will be registered. BSJ officers also monitor the company's facilities on a continuous basis and routinely tests products on supermarket shelves to ensure quality and safety.

The ministry always welcomes well-thought-out and executed research. Based on the information we were provided and what was reported in the press, we argue that this research carried out by the NCU team must be considered preliminary at best as it assigns cause and effect without elimination of other possible causal factors.

The ministry awaits the release of the final report which we hope will conform to the usual high standards of the NCU.

Frankly, such a study is not helpful to the advancement of agriculture, especially at a time when we are trying to make the sector a significant industry - one that is market-driven, provides our citizens with healthy, affordable and locally grown alternatives to imported foods.