RTCR 485:2016. CHEMICAL SUBSTANCES. FERTILIZERS AND AMENDMENTS FOR AGRICULTURAL USE. TOLERANCES AND PERMITTED LIMITS FOR THE CONCENTRATION OF ELEMENTS AND CONTAMINANTS 1. PURPOSE The purpose of this technical regulation is to establish the tolerances and permitted limits for the concentration of elements, heavy metals and impurities in fertilizers and amendments, including raw materials registered for commercialization in Costa Rica.
2. SCOPE OF APPLICATION The provisions of this regulation apply to fertilizers, amendments and raw materials registered for agricultural use in Costa Rica.
3. REFERENCES 3.1. Executive Decree No. 39733-COMEX-MEIC-MAG, Publication of Resolution No. 374-2015 (COMIECO-LXXIV) dated April 21, 2016 and its annex: Central American Technical Regulation RTCA 65.05.54:15 Fertilizers and amendments for agricultural use. Requirements for their registration and its errata published in La Gaceta No. 115 Alcance 98 of June 15, 2016.
3.2. Executive Decree No. 27973-MAG-MEIC-S, RTCR 318:1998 LABORATORY FOR ANALYSIS OF CHEMICAL AND BIOLOGICAL SUBSTANCES FOR USE IN AGRICULTURE. Published in La Gaceta of July 19, 1999.
3.3. Executive Decree No. 27041-MAG-MEIC, RTCR 176: 1991. AGROCHEMICALS. SAMPLING. Published in La Gaceta of September 9, 1998.
4. DEFINITIONS 4.1 contaminants: are substances, heavy metals or impurities that fertilizers and amendments may contain due to their presence in the raw material or as a product of the manufacturing process, which could cause some problem to the agricultural system, the environment or people's health.
4.2 minor element (micronutrient): elements B, Cu, Mn, Mo, Zn, Fe and Co, essential for plant growth in small quantities compared to the principal elements.
4.3 principal element (macronutrient, major or primary element): elements essential for plants N, P and K.
4.4 secondary element: elements essential for plants Ca, Mg, S, which are required in a smaller proportion than the principal elements.
4.5 total element: total concentration of the nutrient soluble in inorganic acids present in a fertilizer.
4.6 inorganic amendment: natural or synthetic inorganic compound (product of an industrial process) that contains elements such as Ca, Mg, and S, primarily used for regulating soil acidity.
4.7 organic amendment: product of organic or biological origin with varying degrees of processing that can modify and improve the physical, chemical and biological properties of the soil. They can be solid or liquid, and applied to the soil or foliage.
4.8 chemical equivalent (equivalente químico, EQ): capacity to neutralize acidity that a material has relative to pure calcium carbonate.
4.9 inorganic fertilizer: inorganic product, natural or synthetic, that applied to the soil or foliage of crops supplies elements necessary for plant growth.
4.10 compound fertilizer: fertilizer that contains at least two nutrients and is obtained chemically or by physical mixture.
4.11 simple fertilizer: fertilizer that contains only one of the nutrients useful for the plant.
4.12 special formula: that which is prepared to satisfy the specific nutritional needs of a crop, on a production unit, which is not commercialized through distribution chains.
4.13 NPK formula: inorganic fertilizer that contains the 3 or at least 2 of the 3 principal elements, N, P2O5 and K2O, and which, for the purposes of this technical regulation, is subject to a particular assessment. It does not include any product that classifies as RAW MATERIAL.
4.14 uncertainty (Guide JCGM 100:2008): parameter associated with the result of a measurement, that characterizes the dispersion of the values that could reasonably be attributed to the measurand or magnitude subject to measurement.
4.15 maximum permitted limit: maximum concentration of a substance that may be present in a fertilizer or amendment.
4.16 lower permitted limit: minimum acceptable concentration of a substance that may be present in a fertilizer or amendment.
4.17 liming material: product based on Ca, Mg or both that is used to neutralize soil acidity. Classifies as an inorganic amendment.
4.18 raw material: natural or synthetic chemical compound that can provide one or several elements and is used to formulate fertilizers.
4.19 registrant: natural or legal person who requests from the Ministry the authorization of a registration for a fertilizer or amendment for agricultural use.
4.20 tolerance: is the admissible difference between the value found in the analysis of the concentration of an element with respect to its declared value, which is expressed in percentage units.
5. ABBREVIATIONS 5.1 DAP: Diammonium phosphate 5.2 Elements and chemical compounds:
5.2.1 As: arsenic 5.2.2 B: boron 5.2.3 Ca: calcium 5.2.4 CaCO3: calcium carbonate 5.2.5 CaO: calcium oxide, expression of calcium in fertilizers 5.2.6 CaSO4: calcium sulfate 5.2.8 Cd: cadmium 5.2.9 Co: cobalt 5.2.10 Cr: chromium 5.2.11 Cu: copper 5.2.12 Fe: iron 5.2.13 Hg: mercury 5.2.14 K: potassium 5.2.15 KCl: Potassium chloride 5.2.16 K2O: potassium oxide, expression of potassium in fertilizers 5.2.17 Mg: magnesium 5.2.18 MgCO3: magnesium carbonate 5.2.19 MgO: magnesium oxide, expression of magnesium in fertilizers 5.2.20 Mn: manganese 5.2.21 Mo: molybdenum 5.2.22 N: nitrogen 5.2.23 P: phosphorus 5.2.24 P2O5: diphosphorus pentoxide, expression of phosphorus in fertilizers 5.2.25 Pb: lead 5.2.26 S: sulfur 5.2.27 Zn: zinc 5.3 EQ: Chemical Equivalent (Equivalente Químico) 5.4 MAP: Monoammonium phosphate 5.5 NPK: N, P2O5 and K2O 5.6 SFE: State Phytosanitary Service (Servicio Fitosanitario del Estado) 5.7 SFT: Triple Superphosphate 6. TOLERANCES AND PERMITTED CONCENTRATION LIMITS FOR THE CATEGORIES ESTABLISHED IN THIS RTCR 6.1 RAW MATERIALS In this category are included all simple or compound conventional sources used to manufacture fertilizers and all those salts based on sulfates, nitrates and phosphates that are used for the formulation of foliar fertilizers (solid or liquid) or for fertigation solutions, or similar. The list of products considered RAW MATERIALS is included in Annex A.
These products can be used directly for application to crops, but if they fit this description, they will be controlled as RAW MATERIALS.
For control purposes, the levels of Cd, Pb, Cr, As, Hg in RAW MATERIALS must not exceed the values established in Table 1-Maximum permitted limit for HEAVY METALS.
Table 1. Maximum permitted limit for HEAVY METALS.
| Element | mg/kg |
|---|---|
| Cd | 80 |
| Pb | 200 |
| Cr | 500 |
| As | 60 |
| Hg | 15 |
When the RAW MATERIAL is urea, it may not contain, for control purposes, a concentration of Biuret exceeding 1.2% by mass, as an impurity.
The reference for controlling RAW MATERIALS is the value declared before the Agrochemical Registration Unit of the SFE, which, for the purposes of this RTCR, will be expressed in percentage terms with one decimal place.
The permitted tolerances in the concentrations of RAW MATERIALS, regardless of the element, will be guided by the criteria established in Table 2-Tolerance Permitted for RAW MATERIALS.
Table 2. Tolerance permitted for RAW MATERIALS.
| Declared concentration (% of element) | Permitted tolerance (in units of the declared concentration) |
|---|---|
| Up to 12 | ± 1.0 |
| Up to 16 | ± 1.1 |
| Up to 20 | ± 1.2 |
| Up to 24 | ± 1.3 |
| Up to 28 | ± 1.4 |
| Up to 32 | ± 1.5 |
| Up to 36 | ± 1.6 |
| Up to 40 | ± 1.7 |
| Up to 44 | ± 1.8 |
| Up to 48 | ± 1.9 |
| Up to 52 | ± 2.0 |
| Up to 56 | ± 2.1 |
| Up to 60 | ± 2.2 |
| Up to 64 | ± 2.3 |
| Up to 68 | ± 2.4 |
| Up to 72 | ± 2.5 |
| Up to 76 | ± 2.6 |
| Up to 80 | ± 2.7 |
| Up to 84 | ± 2.8 |
| Up to 88 | ± 2.9 |
| More than 88 | ± 3.0 |
6.2 INORGANIC FERTILIZERS The products included in this category may be liquid or solid (granular, crystalline or powder), and presented in chemical formulation or physical mixture, or with any other type of additive that regulates their availability to the plant (compounds that promote slow release, inhibitors of some nutrient transformation process or similar).
For control purposes, the levels of Cd, Pb, Cr, As, Hg in INORGANIC FERTILIZERS must not exceed the values established in Table 1-Maximum permitted limit for HEAVY METALS.
In the case of formulas containing urea, the same Biuret criterion established in section 6.1 applies.
For the control of inorganic fertilizers, the chemical analysis must include the total concentrations of all elements (N, P2O5, K2O, MgO, B, CaO, S or other) that are present in the formula at more than 0.5%, with the exception of B and Zn, which will be controlled starting at 0.2%, in percentage terms and with one decimal place.
For tolerance purposes, a distinction is made between:
6.2.1 NPK FORMULAS. The tolerance of NPK FORMULAS that include at least 2 of these major elements and that are not RAW MATERIALS (section 6.1) must be evaluated taking into consideration two criteria jointly according to the tolerances indicated in Table 3-Permitted tolerance for INORGANIC FERTILIZERS - NPK FORMULAS.
The two criteria that must be considered jointly are:
. the sum of these 2 or 3 elements (N+P2O5+K2O) in their conventional percentage expression.
. and the concentration of each of the elements, N, P2O5 and K2O, individually.
Table 3. Tolerance permitted for INORGANIC FERTILIZERS - NPK FORMULAS.
| Declared concentration (% of element) | Permitted tolerance (in UNITS of the declared concentration) | |||
|---|---|---|---|---|
| For the evaluation of the sum of N+P2O5+K2O | For the individual evaluation of N, P2O5 and K2O | |||
| Up to 12 | -1.0 | 4.0 | -1.0 | 4.0 |
| Up to 16 | -1.1 | 4.7 | -1.2 | 4.7 |
| Up to 20 | -1.2 | 5.4 | -1.4 | 5.4 |
| Up to 24 | -1.3 | 6.1 | -1.6 | 6.1 |
| Up to 28 | -1.4 | 6.8 | -1.8 | 6.8 |
| Up to 32 | -1.5 | 7.5 | -2.0 | 7.5 |
| Up to 36 | -1.6 | 8.2 | -2.2 | 8.2 |
| Up to 40 | -1.7 | 8.9 | -2.4 | 8.9 |
| Up to 44 | -1.8 | 9.6 | -2.6 | 9.6 |
| Up to 48 | -1.9 | 10.3 | -2.8 | 10.3 |
| Up to 52 | -2.0 | 11.0 | -3.0 | 11.0 |
| Up to 56 | -2.1 | 11.7 | -3.2 | 11.7 |
| Up to 60 | -2.2 | 12.4 | -3.4 | 12.4 |
| Up to 64 | -2.3 | 13.1 | -3.6 | 13.1 |
| Up to 68 | -2.4 | 13.8 | -3.8 | 13.8 |
| Up to 72 | -2.5 | 14.5 | -4.0 | 14.5 |
| Up to 76 | -2.6 | 15.2 | -4.2 | 15.2 |
| Up to 80 | -2.7 | 15.9 | -4.4 | 15.9 |
| Up to 84 | -2.8 | 16.6 | -4.6 | 16.6 |
| Up to 88 | -2.9 | 17.3 | -4.8 | 17.3 |
| More than 88 | -3.0 | 18.0 | -5.0 | 18.0 |
6.2.2. FORMULAS WITH OTHER ELEMENTS. The elements present in other inorganic formulas that are not those described in sections 6.2.1-NPK FORMULAS, 6.1-RAW MATERIALS and 6.4-INORGANIC AMENDMENTS and that have been declared, must comply individually with the tolerances established in Table 4-Permitted tolerance for INORGANIC FERTILIZERS - FORMULAS WITH OTHER ELEMENTS. Also included in this category are the additional elements that are present in NPK FORMULAS, namely, MgO, B, S, CaO, Zn, or any other declared.
Table 4. Tolerance permitted for INORGANIC FERTILIZERS - FORMULAS WITH OTHER ELEMENTS
| Declared concentration (% of element) | Permitted tolerance (in UNITS of the declared concentration) | |
|---|---|---|
| Up to 0.6 | -0.3 | 1.2 |
| Up to 1 | -0.4 | 1.6 |
| Up to 2 | -0.5 | 2.0 |
| Up to 4 | -0.6 | 2.4 |
| Up to 6 | -0.7 | 2.8 |
| Up to 8 | -0.8 | 3.2 |
| Up to 10 | -0.9 | 3.6 |
| Up to 12 | -1.0 | 4.0 |
| Up to 16 | -1.1 | 4.7 |
| Up to 20 | -1.2 | 5.4 |
| Up to 24 | -1.3 | 6.1 |
| Up to 28 | -1.4 | 6.8 |
| Up to 32 | -1.5 | 7.5 |
| Up to 36 | -1.6 | 8.2 |
| Up to 40 | -1.7 | 8.9 |
| Up to 44 | -1.8 | 9.6 |
| Up to 48 | -1.9 | 10.3 |
| Up to 52 | -2.0 | 11.0 |
| Up to 56 | -2.1 | 11.7 |
| Up to 60 | -2.2 | 12.4 |
| Up to 64 | -2.3 | 13.1 |
| Up to 68 | -2.4 | 13.8 |
| Up to 72 | -2.5 | 14.5 |
| Up to 76 | -2.6 | 15.2 |
| Up to 80 | -2.7 | 15.9 |
| Up to 84 | -2.8 | 16.6 |
| Up to 88 | -2.9 | 17.3 |
| More than 88 | -3.0 | 18.0 |
6.3 ORGANIC AMENDMENTS These products are the result of biological processes, highly dependent and variable according to moisture content and a series of other external conditions. Their effect on the soil and crops goes beyond the direct supply of nutrients, so the chemical analysis of their concentrations constitutes a characterization criterion rather than a valuation.
This category includes processed plant and animal residues, compost, bocashi, sludges and effluents, biols or bioferments, plant extracts, teas, leachates, provided they include some nutrient in concentrations greater than 0.5%. Organic amendments can be reinforced with inorganic fertilizers.
Biological products that include living organisms, such as decomposer microorganisms, N fixers, solubilizers, mycorrhizae and organic compounds such as humic acids, fulvic acids, algae, amino acids, vitamins, hormones, biostimulants and similar, are outside this regulation.
For control purposes, the levels of Cd, Pb, Cr, As, Hg in ORGANIC AMENDMENTS must not exceed the values established in Table 1-Maximum permitted limit for HEAVY METALS.
For the control of organic amendments, the analysis must include the elements present at more than 0.5% expressed as total concentrations in dry weight (80°C), in percentage terms with one decimal place and only the minimum permitted limit will be considered. The accepted tolerance for these ORGANIC AMENDMENTS will be guided by the criteria established in Table 5-Minimum permitted limit for ORGANIC AMENDMENTS.
Table 5. Minimum permitted limit for ORGANIC AMENDMENTS.
| Declared concentration (% of element) | Minimum permitted (in UNITS of the declared concentration) |
|---|---|
| Up to 0.5 | -0.2 |
| Up to 1.0 | -0.3 |
| Up to 1.5 | -0.4 |
| Up to 2.0 | -0.5 |
| Up to 2.5 | -0.6 |
| Up to 3.0 | -0.7 |
| Up to 3.5 | -0.8 |
| Up to 4.0 | -0.9 |
| Up to 5.0 | -1.1 |
| Up to 6.0 | -1.3 |
| Up to 7.0 | -1.5 |
| Up to 8.0 | -1.7 |
| Up to 10.0 | -2.1 |
| Up to 12.0 | -2.5 |
| More than 12.0 | -2.9 |
6.4 INORGANIC AMENDMENTS In this category are included all inorganic products used to amend soils, that is, to cause an integral effect on it, mainly directed towards the regulation of soil acidity or basicity.
They may come directly from natural deposits or be formulated individually or in a mixture, ground (powdered) or granular, and contain elements such as Ca and Mg in the form of oxide, hydroxide or carbonates, and S in oxidized or elemental form.
For control purposes, the levels of Cd, Pb, Cr, As, Hg in INORGANIC AMENDMENTS must not exceed the values established in Table 1-Maximum permitted limit for HEAVY METALS.
For INORGANIC AMENDMENTS, the analysis of the total chemical composition of the elements CaO, MgO and S or any other present in the INORGANIC AMENDMENT in concentrations greater than 1%, expressed in percentage form and with one decimal place, will be assessed according to the criteria established in Table 6-Minimum permitted limit for INORGANIC AMENDMENTS.
Table 6. Minimum permitted limit for INORGANIC AMENDMENTS.
| Declared concentration (% of element) | Minimum permitted (in UNITS of the declared concentration) |
|---|---|
| Up to 12 | -1.0 |
| Up to 16 | -1.1 |
| Up to 20 | -1.2 |
| Up to 24 | -1.3 |
| Up to 28 | -1.4 |
| Up to 32 | -1.5 |
| Up to 36 | -1.6 |
| Up to 40 | -1.7 |
| Up to 44 | -1.8 |
| Up to 48 | -1.9 |
| Up to 52 | -2.0 |
| Up to 56 | -2.1 |
| Up to 60 | -2.2 |
| Up to 64 | -2.3 |
| Up to 68 | -2.4 |
| Up to 72 | -2.5 |
| Up to 76 | -2.6 |
| Up to 80 | -2.7 |
| Up to 84 | -2.8 |
| Up to 88 | -2.9 |
| More than 88 | -3.0 |
The analysis of % Moisture of the INORGANIC AMENDMENT must not be greater than 10% (MCS-Massachusetts Court System).
A list of the products considered INORGANIC AMENDMENTS is noted in Annex A.
7. SAMPLING Sampling of fertilizers for control must be governed according to Executive Decree No. 27041-MAG-MEIC, RTCR 176:1991. Agrochemicals. Sampling.
8. METHODS OF ANALYSIS FOR THE VERIFICATION OF THE ESTABLISHED TOLERANCES AND LIMITS The concentration of the elements in the materials contemplated in this regulation must be analyzed by a method that provides the total mass/mass concentration (with the exception of potassium, which can also be analyzed as water-soluble), both in solids and liquids. For the purposes of this RTCR, the expression of the concentrations will be assessed in percentage terms with one decimal place.
The methods used are the conventional ones for the determination of total concentrations of elements, which consist of digestion procedures with strong acids (such as Nitric Acid, Hydrochloric Acid, or a mixture of both) and determinations by Colorimetry, Flame Photometry, Absorption Spectroscopy or Atomic Emission Spectroscopy, according to what each laboratory has validated. K2O is the only exception, as it can be declared as water-soluble or as total.
The detail of the accepted methodologies is established in Annex B.
The tolerances or limits included in this regulation globally consider the admissible differences that may occur throughout the entire process, namely, the variation that may occur during the manufacturing process, during sampling and due to the analytical method employed, that is, the margins defined in this regulation are including all sources of variation that make up the uncertainty.
9. COMPETENT AUTHORITY In order to give national operability to this regulation, the fertilizers and amendments registered in Costa Rica will be controlled by the State Phytosanitary Service (Servicio Fitosanitario del Estado), in order to verify that they comply with the provisions of this RTCR.
Any person who, when using this standard, finds typographical, orthographic errors, inaccuracies or ambiguities, is requested to notify the State Phytosanitary Service (Servicio Fitosanitario del Estado) without delay, providing, if possible, the corresponding information, to make the necessary investigations and take the case provisions.
10. CONCORDANCE This document does not coincide with any international standard because no such standard exists at the time of elaboration of this regulation.
11. BIBLIOGRAPHY 11.1 AFPC-Association of Fertilizer and Phosphate Chemists. 2014. Available at: http://afpc.net/.
11.2 AOAC-Association of Official Analytical Chemists. 2012. AOAC INTERNATIONAL Official Methods of Analysis, 19th Edition. Available at: http://www.aoac.org/iMIS15_Prod/AOAC_Member/Member_Home.aspx 11.3 Spanish Association for Standardization and Certification. (May 1994). Spanish Standard: Fertilizers and soil conditioners. Classification. Equivalent to ISO 7851:1983. Madrid, Spain.
11.4 BERTSCH, F. 1998. Soil fertility and its management. San José, Costa Rica, ACCS. 157 p.
11.5 Fertilizer Industry Federation of Australia. (March 2011). National Code of Practice for Fertilizer Description of Labeling. Australia.
11.6 Ecuadorian Institute for Standardization. (April 1997). Ecuadorian Technical Standard NTE INEN 209:1998 Fertilizers or Manures. Definitions. I, 2-9. Quito, Ecuador.
11.7 MAGRUDER FERTILIZER Check Sample Program, 2014. The Association of American Plant Food Control Officials AAPFCO, The Association of Fertilizer and Phosphate Chemists AFPC, The Fertilizer Institute TFI and AOAC, Intl. Available at: http://www.magruderchecksample.org/ 11.8 MCS-Massachusetts Court System, 330 CMR 15.00: COMMERCIAL FERTILIZER AND LIME. Available at: http://www.mass.gov/eea/docs/agr/legal/regs/330-cmr-15-00.pdf 11.9 Ministry of the Presidency, Spain. (July 19, 2005). Royal Decree 824/2005. Official State Gazette (171), 25592-25669.
11.10 Ministry of the Presidency, Spain. (July 10, 2013). Royal Decree 506/2013. Official State Gazette (164), 51119-51207.
11.11 MOLINA, E. 1998. Liming for the correction of soil acidity. 1 ed. San José, Costa Rica, ACCS. 45 p.
11.12 Joint Committee for Guides in Metrology: BIPM, IEC, IFCC, ILAC, ISO, IUPAC, IUPAP and OIML. 2008. Guide JCGM 100:2008, Evaluation of measurement data - Guide to the expression of uncertainty in measurement. I Edition. pp. 2.
11.13 European Parliament and the Council of the European Union. (November 2003). Regulation (EC) No 2003/2003. Luxembourg.
11.14 Sine, C., & Mortvedt, J. J. (1995). Fertilizer Dictionary. In R. T. Mesiter, & C. Sine, Farm Chemicals Handbook '95 (Vol. 81, pp. B1-B81). Willoughby, Ohio, United States of America: Meister Publishing Company.
11.15 Executive Decree No. 37982-COMEX-MEIC-MAG, RTCA 65.05.54:09 FERTILIZERS AND AMENDMENTS FOR AGRICULTURAL USE. REQUIREMENTS FOR REGISTRATION. Published in La Gaceta of November 12, 2013.
*Methods recommended by the Agrochemical Quality Control Laboratory.
The preceding list is presented as a reference for the application of chemical analysis methodologies for fertilizers; likewise, the Agrochemical Quality Control Laboratory will update it periodically on the SFE internet page. In the event that the method implemented by the industry is not one of the reference ones, the registrant must prove before the Department of Agrochemicals and Equipment that they have evidence of having carried out the respective validation, providing the technical information.
END OF THE TECHNICAL REGULATION