Development and certification of the new SRM 695 trace elements in multi-nutrient fertilizer

Abstract

During the past seven years, several states within the US have enacted regulations that limit the amounts of selected non-nutritive elements in fertilizers. Internationally, several countries, including Japan, China, and Australia, and the European Union also limit the amount of selected elements in fertilizers. The elements of interest include As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Se, and Zn. Fertilizer manufacturers and state regulatory authorities, faced with meeting and verifying these limits, need to develop analytical methods for determination of the elements of concern and to validate results obtained using these methods. Until now, there were no certified reference materials available with certified mass fraction values for all elements of interest in a blended, multi-nutrient fertilizer matrix. A new standard reference material (SRM) 695 trace elements in multi-nutrient fertilizer, has been developed to help meet these needs. SRM 695 has recently been issued with certified mass fraction values for seventeen elements, reference values for an additional five elements, and information values for two elements. The certificate of analysis includes an addendum listing percentage recovery for eight of these elements, determined using an acid-extraction inductively-coupled plasma optical-emission spectrometry (ICP-OES) method recently developed and tested by members of the Association of American Plant Food Control Officials.

X-ray Spectrometry

“…Certified values for 17 elements (As, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Ni, Pb, Na, V, and Zn) were reported. Reference values for Al, B, N, P, and Se, and information values for Cl and Ti were also provided (221). The National Geophysical Research Institute (NGRI, India) prepared one high-grade gold geochemical CRM (BND 3401.01) from 350 kg of a sulfide-bearing quartz vein located in sheared acid volcanic rock.…”

Portable X-ray fluorescence (pXRF) calibration for analysis of nutrient concentrations and trace element contaminants in fertilisers

“…Studies at Rothamsted Research showed that long-term use of superphosphate fertilisers in the Park Grass experiment increased the Cd content of soil and herbage compared with control conditions, and that cadmium can remain plant available for up to one hundred years [ 8 , 9 ]. Therefore, many countries including the USA, Japan, China, Australia and several European countries have regulations which limit the amount of selected non-nutritive elements in fertilisers, particularly As, Cd, Co, Cr, Pb and Hg [ 10 ]. Since 2019, the EU also has requirements to measure trace element contents in fertilisers and conform to limits [ 11 ].…”

“…X-ray fluorescence (XRF) analysis of materials with a wide range of elemental contents can give comparable results to those obtained by conventional techniques in inorganic materials [ 12 – 17 ], as well as organic materials [ 18 , 19 ] and fertilisers [ 10 , 20 – 22 ]. Additionally, pXRF instruments are now available and can be used in-situ for quality control and environmental assessments, yet still have performance levels approaching those of benchtop devices [ 16 , 17 ].…”

Micronutrientes e metais pesados tóxicos: do fertilizante ao produto agrícola

“…As composições das soluções nutritivas (Tabela 9) foram definidas por meio de ensaios teste com plantas de arroz e, também, baseadas nas soluções de Johnson et al (1957) e Hart et al (2005 Vale destacar, que no presente trabalho, as quantificações de todos os elementos foram realizadas de modo quase simutâneo (por ICP-MS) nos mesmos extratos, referentes à cada método. Já os valores certificados e de referência da amostra NIST foram estabelecidos individualmente para cada elemento, quanto à extração e à quantificação que melhor se adequou a cada caso (MACKEY et al, 2007).…”