This document evaluates heavy metal contamination in Cuban soils, emphasizing the importance of monitoring for food safety and agricultural product certification. It details sources of heavy metals, sampling methods, and provides reference values based on analytical techniques to assess risks. The Cuban soil service is developing a preliminary methodology for evaluating these contaminants to safeguard soil quality for future generations.

2. Olegario Muñiz Ugarte1
Mirelys Rodríguez Alfaro1
Alfredo Montero Álvarez2
1Soil Institute, MINAG, Cuba
2CEADEN, CITMA, Cuba
Heavy Metals (H.M) Soil
Evaluation in Cuba, a case
study

3. Soil Atlas for Latin America and the Caribbean (2014)
Using the World Reference Base (WRB) Soil Classification

4. Heavy Metals in soils
Food Security is of highest
priority for the Cuban Ministry
of Agriculture (MINAG) and
special attention must be paid
to the safety and quality
certification of products of
agricultural origin, avoiding the
risk to human health that can
cause the toxic contaminants,
including Heavy Metals (HM)
SOIL
QUALITY

5. HM SOURCES IN SOILS:
• Parental Material
• Mineral Fertilizers (rock
phosphate, etc)
• Pesticides
• Organic manures
• Water and Sludges
• Mines and metalurgical industries
• Fosil Fuel Combustion
Perfil 2

6. The elements determined were mainly :
Cd, Pb, Ni, Cr, Zn , Cu, As, Hg, Sb
For many years
Total contents
were determined .
In present, USEPA
3051a
Microwave

7. During these years the
Analytical Techniques
were improved

8. The surveys carried out in Cuba show that only in
some areas of intensive agriculture where during
many years High Inputs where employed (fertilizers,
pesticides, machinery, etc), some of these HM
contents, despite that can not be considered an
inminent risk for human health, are higher than the
International Mean Values (Muñiz et al, 1988, 2000
y 2004).
It is the case of Red Ferralític soil
(Nitisols, WRB) areas in Artemisa,
Mayabeque and Matanzas
provinces
Perfil 2

9. FERRASOLS
LUVISOLS
CAMBISOLS
CARSO DESNUDO
Fuente: CNSF - MINAGRI
SUELOS
RENDSINA
VERTISOLS
GLEYSOLS
FLUVISOLS
ARENOSOLS
LITOSOLS

0 50 100
Kilómetros
Ni and Cr
Cuban soils developed
from Serpentinite rock
are characterized for Ni
and Cr contents that can
reach values of 2000.0
mg.Kg-1. In others
developed from
sedimentary limestone, Ni
and Cr content could be
200.0 mg.Kg-1
Soil Exch. Organic Fe amorphus Fe cristal. Total
1 1.66 9.67 1.84 20.84 196.2
2 1.95 9.82 1.48 10.40 160.6
Table. Ni fractions in Red Ferralític soil (mg.Kg-1) by Shuman (1988)
Source: Muñiz et al, 2008 .

10. 0,02
0,01
0,03
0,07
0,01
0,01
0,03
0,1
0,05
0,01
0,04
0,03
0,05
0,01
0,04
0,04
0
0,02
0,04
0,06
0,08
0,1
0,12
0,14
0,16
mg/pl
Kuban 2
56 ddg
Bayama
56 ddg
Kuban 2
69 ddg
Bayama
69 ddg
Máquina y momento
Hojas
Tallos
Raíz
Tubérculo
Figure 1. Cd uptake (mg/plant) in two stages of the potato cycle
(Red Ferralitic soil) , Muñiz et al, 2004.

11. Gráfico 3. Pb Uptake for beans and tomato (Red
Ferralític Soil), Muñiz et al, 2004.
0,211
0,081 0,299
0,058
1,722
0,32
0
0,5
1
1,5
2
2,5
mg/pl
Frijol negro Frijol rojo Tomate
Cultivo
Fruto
Resto

12. 1. CRITERION FOR THE EVALUATION OF HM
IN ORGANIC MANURES AND COMPOSTS
2. PERMISSIBLE LIMITS of HM IN SOILS
Studies developed

13. Organic manures are in present an important source of nutrients
in Cuban Agriculture (Urban Agriculture) and thus, HM must be
monitored
ORGANOPONICS

14. HM criterion for the evaluation of Organic Manures.
Source Cd Pb Ni Zn Cu
Vermicompost < 0.40 17 130 170 34
Compost 0.60 30 110 205 85
Correlation between HM
content in the Organic
Manure and the HM
content in crop (leaf and
fruit vegetables)
considering Codex Stan
192-1995 (2016) as
benchmark.
Tabla. Mean content of HM in differents sources of organic manures (mg.Kg-1)
H.M.
Preliminary range of
Permissible Limits on Organic
Manure
Cd 2-3 mg Kg-1
Pb 140-150 mg Kg-1

15. Use of Urban Solid Residues (USR) compost
Cd Pb Ni Zn
2.00 380 180 530
Tabla. HM content in composts of USR
(mg.Kg-1)
Source: Muñiz et al (2008) .

16. PERMISSIBLE LIMITS of HM IN SOILS
by CONAMA(2009)
Reference Values (RV): natural values in the different
types of soils (due to the parental material) according CETESB (2005)
Prevention Values (PV): values between RV and IV. Must
be monitored
Investigation Values (IV): values over which exist a risk
for human health and life (not alowed for crops) Based in Risk Analysis,
using Csoil software, according Brand et al. (2007).

17. For the determination of Reference Values (RV):
Samples: 35 Reference Profiles along
the country (0-20 cm)
The profiles were selected
considering the Map escale 1: 25 000,
in areas with no anthropic activity

18. Heavy Metals n (1) n (2) RV Mean Mínimum Maximum s
Cd (mg kg-1) 33 3 0,6 1,2 0,1 6,1 1,6
Pb (mg kg-1) 33 1 50 34,6 5,2 113,6 23,6
Zn (mg kg-1) 33 4 86 90,7 26,1 260,1 54,3
Cu (mg kg-1) 33 5 83 83,7 9,5 269,9 54,5
Ni (mg kg-1) 33 4 170 294,2 9,8 3030,8 567,6
Cr (mg kg-1) 33 7 153 463,2 9,9 4418,3 941,8
Table 2. Reference Values(RV), mean values, minimum and maximum and
deviation standard on soil HM in Cuba
n (1) total of samples used for obtaining RVs
n (2) total of samples eliminated from the boxplot
Reference Values(RV):

19. Element RV PV IV
Cd 0,6 2.0 3.0
Pb 50 115 180
Zn 86 300 450
Cu 83 150 200
Ni 170 400 600
Cr 153 300 400
In 2016, we began a National Project with IAEA support
with the aim of Strengthening national capacities for the
certification of soil quality and safety assurance of
agricultural products through applications of nuclear
and conventional techniques
Reference Values (RV) and Investigation Values (IV):

20. CONCLUSIONS
Cuban Soil Service has in present, a
methodology, still preliminary, for the
evaluation of Heavy Metals in agricultural
soils and organic manures

21. THANKS
SOIL is our main
natural resource
and thus, we
must preserve it
for future
generations