The Quality of Fertilizer Traded in West Africa: Evidence for Stronger Control
Loading...
Date
2013-03
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
The Commissions of the Economic Community of the West African States (ECOWAS) and the West Africa Economic and Monetary Union (UEMOA) are developing a regional legal framework for controlling the quality of fertilizer traded in West Africa. The main purpose of this framework is to safeguard the interests of farmers against nutrient deficiencies, adulteration, misleading claims and short weight as well as to contribute to the creation of an enabling environment for private sector investment in the fertilizer industry. To determine the basis for assessing the effectiveness of this framework when it is implemented, the ECOWAS and UEMOA Commissions initiated, through the Marketing Inputs Regionally (MIR) Plus project, a study to assess the quality of fertilizer traded in West Africa as well as factors influencing fertilizer quality. The study was carried out by trained inspectors from the national fertilizer regulatory services in five West African countries – Côte d’Ivoire, Ghana, Nigeria, Senegal and Togo. The sampling methodology consisted of two steps. The first step focused on obtaining a random sample of 5 to 10 percent of fertilizer dealers in each country either from maps (Ghana and Nigeria) geo-referencing the location of each dealer or with lists of dealers available at the ministry of agriculture (Côte d’Ivoire, Senegal and Togo). The second step was the collection of random samples of fertilizers from each of the dealers selected in the first step. Fertilizer sampling and collection was done following an agreed-upon protocol. In addition, pretested questionnaires were used to record conditions of storage, physical attributes of fertilizers and characteristics of markets and dealers. A total of 2,028 fertilizer samples was collected from the 827 wholesalers, government depots and retailers of various sizes in the five countries. The distribution of these fertilizer samples is a good representation of the relative importance of the different fertilizer products in the five countries. Urea and the NPK 15:15:15 blend were the only products collected from each of the five countries. Urea, the compound NPK 15:15:15, the compound NPK 16:16:16, the compound NPK 23:10:5, the blend NPK 15:15:15 and ammonium sulfate (AS) account for 79 percent of the samples collected. The chemical analyses of the fertilizer samples focused on determining the content of primary plant nutrients (total nitrogen, available phosphorus and soluble potassium). However, few samples were considered for determination of secondary nutrients (calcium [Ca], magnesium [Mg] and sulfur [S]). Statistical analyses were applied to data on nutrient contents, physical attributes and characteristics of markets, dealers and storage conditions to determine the quality of the different fertilizer products and to associate fertilizer quality with market and dealer characteristics. To be meaningful, the nutrient content compliance was analyzed statistically only for the fertilizer products with at least 23 samples and these accounted for 93 percent of all the samples collected in the study. Nutrient content compliance was assessed based on newly adopted ECOWAS standards. Blends and Compounds Present Cases of Poor Quality, but This is Most Severe for Blends The chemical analyses carried out show that NPK fertilizers manufactured through blending present the most frequent and severe cases of poor quality compared with compound products. More specifically, 51 percent of the 106 samples of the 15:15:15 blend were out of compliance with respect to newly adopted ECOWAS tolerance limits for nutrient content deviations. Similarly, 86 percent of the 90 samples of the blended 20:10:10, 12 percent of the 30 samples of the blended 6:20:10, 96 percent of the 27 samples of the blended 15:10:10, 31 percent of the 23 samples of Asaase Wura (0:22:18+9CaO+7S+5MgO) and 26 percent of the 27 samples of Cocoa Feed (0:30:20) failed to meet the ECOWAS quality standards. In contrast, compared with blended products, only 4 percent of the 534 samples of urea, 10 percent of the 356 samples of the compound 15:15:15, 16 percent of the 162 samples of AS (21:0:0+24S), 15 percent of the 162 samples of compound 16:16:16, 1 percent of the 103 samples of compound 23:10:5 and 4 percent of the 90 samples of Sulfan (24:0:0+6S) failed to meet the ECOWAS quality standards. While the proportions of non-compliant samples observed in the compound products is lower than the ones observed in blended products, these can still be considered high for imported products. This result confirms the finding of a previous assessment carried out in 1995 indicating that 10 of the 29 samples of NPK compounds examined were nutrient-deficient. Of the 10 samples of single superphosphate (SSP) collected from several locations in Nigeria, seven of them were found to contain no P2 O5 but contained mainly quartz (SiO2 ). The chemical and X-ray mineralogical analyses indicate that the samples with no phosphorus come from spurious materials without fertilizer characteristics that are commercialized as SSP. Country-to-Country Comparisons Show Variable Product Quality Country-to-country comparisons made between Côte d’Ivoire, Ghana and Togo for the blended 15:15:15 and between Ghana, Nigeria and Togo for the compound 15:15:15 show a great deal of variability between countries. The overall out-of-nutrient content compliance for the blended 15:15:15 was the highest in Côte d’Ivoire (87 percent), followed by Ghana (42 percent) and Togo (6 percent). For the compound 15:15:15, the overall out-of-nutrient content compliance was highest in Nigeria (16 percent), followed by Ghana (10 percent) and Togo (3 percent). The low proportion of non-compliant samples observed in Togo may be attributed to the fact that, of the three countries, Togo might be expected to have low variability in the importation sources and a relative simple distribution chain due to government control of importation and distribution. Nutrient Deficiencies in Blended Products are Not Simply an Issue of Segregation The analysis indicated that the main reason for nutrient content deficiencies in Asaase Wura is the uneven distribution of nutrients in the fertilizer bags caused by granule segregation. Nutrient content deficiencies are also attributed to segregation of the fertilizer components used in the bulk blend for half of the 15:15:15, two-thirds of the Cocoa Feed and one-third of the 6:20:10 blend samples. These results suggest that the high proportion of nutrient-deficient cases found in these products can be avoided using fertilizers of uniform granule size for the manufacture of these blends and utilizing appropriate equipment and procedures to make the blends. The effect of segregation in the NPK blends 15:10:10 and 20:10:10 which have the highest proportion of non-compliant samples is found to be minimal. This indicates that the lack of nutrient compliance in these products is mainly explained by insufficient nutrient input in the blend manufacture. Evidence of Adulterated Products in the Collected Samples is Weak Trained inspectors reported evidence of adulteration in 31 of 134 (23 percent) samples from Côte d’Ivoire but only 14 of 414 (3.4 percent) samples from Nigeria. However, the only cases of completely proven adulteration are the seven samples of SSP from Nigeria that were found to have no P2 O5 content nor any of the minerals that carry P in phosphate rock. Short Weight Fertilizer Bags are Common in the Market An analysis of the weight of 1,055 fertilizer bags collected from all five countries indicates that there is a 41 percent chance that the bag weight does not comply with the ECOWAS tolerance limit in Nigeria, a 28 percent chance for this to occur in Côte d’Ivoire, 13 percent in Senegal, 12 percent in Ghana and 7 percent in Togo. The two probable reasons for underweight bags are poor process control or deliberate acts of underweighting. Market Characteristics are Associated with the Quality of Products Statistically significant association between market characteristics and fertilizer quality categories (good or bad) was found only for 15:15:15 blends when samples from all countries were combined. This was probably because, under this scenario (aggregating samples), there is enough variability in the samples collected between the two categories “Bad” and “Good” for this particular product. The rural markets are associated with significantly higher percentage (87.5 percent) of Good quality fertilizer than the urban markets (56.5 percent). Statistical analysis results also showed that permanent markets tend to have a significantly higher percentage of Good quality of the 15:15:15 blends than periodic markets. Similarly, markets with high concentration of agro-dealers tend to have a significantly higher percentage of Good quality products than isolated agro-dealers. When data was analyzed by country, the pattern of the associations between market characteristics and fertilizer quality differed from the identified when the aggregated data from the five countries was analyzed. This was either because some associations could not be evaluated due to insufficient sample size or because of insufficient quality variability within fertilizers with appropriate sample size. With country-level analysis, statistically significant association between market characteristics and fertilizer quality categories (good or bad) was found only for the 15:15:15 blend in Ghana and for the 15:15:15 compound in Nigeria. In Nigeria, the urban markets showed significantly higher frequency of good quality than the rural markets. In Ghana, the permanent markets, and the dealers that sell mainly to large scale farmers presented significantly higher frequency of good quality than temporary markets and dealers that sell mainly to small scale farmers, respectively. Licensing and Knowledge of Fertilizers Matter Statistical analysis performed on 106 samples of the blended 15:15:15 and agro-dealer characteristics reveals that agro-dealers with “good knowledge about fertilizers” are more likely to sell a higher percentage of Good quality products than the others. Similarly, analyses carried out with the 624 samples of 15:15:15 blends, 15:15:15 compounds and 16:16:16 compounds show that the agro-dealers with a license for selling fertilizer are more likely to sell a higher percentage of Good quality fertilizers than nonlicensed ones. In addition, the analysis also indicates that the agro-dealers that predominantly sell fertilizer to large-scale farmers are more likely to sell a higher percentage of Good quality products than the agro-dealers who sell fertilizer mainly to small-scale farmers. Wholesalers have a significantly higher percentage of Good quality fertilizers than retailers. Physical Attributes of Fertilizers are Associated with Product Quality as Well The qualitative assessment of granule integrity (presence of fine particles and dust) indicated that all the blended fertilizers had at least 50 percent of the samples classified at medium- or high-level categories for the presence of fine particles. The 15:10:10 blend also had 80 percent of dust presence at the high category. Among the compound fertilizers, 16:16:16, 15:15:15, 23:10:5 and Sulfan also presented more than 50 percent of the samples classified in the categories of Medium and High for presence of fine particles. Paradoxically, granule integrity was found poorer for compound 15:15:15 than for the blended 15:15:15. Unfortunately, this lack of granular integrity has a negative impact on the fertilizer’s quality. The observed frequent and severe granule degradation identified can be attributed to excessive manipulation of the fertilizer bags associated with their manual and individual handling. There is also a clear tendency of complex distribution chains (Nigeria and Ghana) to present higher frequency and severity of granular degradation than simple distribution chains (Togo). As expected, the study found a strong correlation between high moisture levels and high caking levels, for both the blended fertilizers and the compound fertilizers. The importance of appropriate bagging was underscored by findings in Senegal where 41 percent of the bags were found to be outer woven without plastic inner lining, and 61 percent of the samples presented medium to high degrees of urea caking. Low frequency of caking in urea was closely associated with use of laminated bags or bags with plastic lining in Ghana, Nigeria, and Togo. Among the physical attributes of fertilizer considered in the study, the moisture content and the segregation showed significant relationships with nutrient content quality only in the 15:15:15 blend. Effective Implementation of the Adopted ECOWAS Fertilizer Regulatory System is Critical The study results clearly suggest that effectively implementing the adopted ECOWAS fertilizer regulatory system is likely to ensure that products supplied to the market meet high quality standards. The system calls for licensing of agro-dealers as well as inspection, sampling and analysis of fertilizers at importation points and along the distribution chain. Addressing the Quality Challenges of the Blends is Needed The fact that blends show the most frequent and severe cases of poor quality suggests that it is imperative to identify the origin of their quality problems and to propose appropriate solutions. In addition, there is a clear need to enhance the manufacturing knowledge and equipment for manufacturing blends. Building the Capacity of Agro-Dealers is Necessary The study results equally suggest the need to train distributors on the appropriate storage and handling of fertilizer products, as well as their physical and chemical properties. Doing so will contribute to reducing the effect of physical attributes of fertilizer on product quality.
Description
Keywords
Chemical Analysis , Fertilizers