Cadmium uptake by onions, lettuce and spinach in New Zealand: Implications for management to meet regulatory limits.
Sci Total Environ
; 668: 780-789, 2019 Jun 10.
Article
en En
| MEDLINE
| ID: mdl-30865908
Paired soil and plant samples collected from the main commercial growing areas for onions (Allium cepa), lettuce (Lactuca sativa) and spinach (Spinacia olearacea) in New Zealand were used to assess the influence of plant and soil factors on cadmium (Cd) uptake in these crops. Differences in Cd concentration between eight lettuce sub-types were not consistent across sites, nor were differences in Cd concentrations in three crisphead cultivars assessed at two sites. Similarly, differences in Cd concentrations between four onion cultivars were inconsistent across sites. Mean lettuce Cd concentrations in eight lettuce varieties (range 0.005-0.034â¯mgâkg-1 (fresh weight, FW) were markedly lower than those in baby leaf and bunching spinach, (range 0.005-0.19â¯mgâkg-1 FW). Significant regional variation was observed in Cd concentrations in one onion cultivar (mean range 0.007-0.05â¯mgâkg-1 FW). Soil Cd concentration, pH and region were statistically significant predictors of onion Cd concentration, explaining low (38% for soil Cd and pH) to moderate (50% for all three parameters) percentage of the variation. Soil Cd concentration and exchangeable magnesium or total carbon were statistically significant predictors of Cd concentration in baby leaf and bunching spinach, respectively, explaining a moderate percentage (49% and 42%) of the variation in Cd concentration. Increasing pH and soil carbon may assist in minimising Cd uptake in onion and bunching spinach, respectively. The low to moderate proportion of explained variation is partly attributable to the narrow range in some measured soil properties and indicates factors other than those assessed are influencing plant uptake. This highlights a challenge in using these relationships to develop risk-based soil guideline values to support compliance with food standards. Similarly, the inconsistency in Cd concentrations in different cultivars across sites highlights the need for multi-site assessments to confirm the low Cd accumulation status of different cultivars.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Contaminantes del Suelo
/
Cadmio
/
Contaminación Ambiental
Tipo de estudio:
Prognostic_studies
Aspecto:
Determinantes_sociais_saude
País/Región como asunto:
Oceania
Idioma:
En
Revista:
Sci Total Environ
Año:
2019
Tipo del documento:
Article
Pais de publicación:
Países Bajos