Abstract
This article aims to identify the extent of the danger of heavy metals that spread in the environment. It is
released into the soil in several ways, which leads to changes in some of its chemical, physical and biological
properties in a way that makes it negatively affect all forms of life on its surface, such as humans, animals and
plants. The danger lies in the fact that it remains in the soil for a long period of time without decomposition or
any chemical change, and it enters into the natural cycle of the environment and is transferred between its various
parts and contents. The article includes the methods of transferring elements from the soil solution contaminated
with them through plant roots, their entry into the plant, and their transport by plant sap to the rest of the plant
parts through the process of transpiration. There are other factors that control the movement of elements within
the tissues of different plants, such as the degree of interaction, oxidation and reduction processes, ionic
competition, hydrolysis, polymerization, and the formation of dissolved salts such as (oxalates and phosphates).
It has inhibitory effects on plants by reducing and delaying growth due to its toxicity, which disrupts various
metabolic activities in cells, such as photosynthesis, respiration, the formation of nucleic acids, the formation of
proteins, as well as the activity and effectiveness of various enzymes and other vital processes that take place
within plants, which ultimately leads to harm to their growth in all its stages and their productive capacity.
Therefore, it poses a threat to life when used as food. The article also highlights the extent to which some plants
growing in environments polluted with heavy metals can store them in their roots while controlling their transfer
from the roots to the stems, leaves and fruits as a type of adaptation to resist the toxicity of these elements. The
greater the amount of heavy metals in the soil, the greater the absorption process by the plant. Plants show
resistance to toxicity to varying degrees by preventing its accumulation in the targeted sites or through the
mechanism of tolerance to these elements when they enter the cytoplasm and when their level increases within
plant tissues. The plant either collects or accumulates them in special locations in the roots, in the vegetative
system, or in the fruits called vesicles, or converts them into other non-toxic forms inside the plant
released into the soil in several ways, which leads to changes in some of its chemical, physical and biological
properties in a way that makes it negatively affect all forms of life on its surface, such as humans, animals and
plants. The danger lies in the fact that it remains in the soil for a long period of time without decomposition or
any chemical change, and it enters into the natural cycle of the environment and is transferred between its various
parts and contents. The article includes the methods of transferring elements from the soil solution contaminated
with them through plant roots, their entry into the plant, and their transport by plant sap to the rest of the plant
parts through the process of transpiration. There are other factors that control the movement of elements within
the tissues of different plants, such as the degree of interaction, oxidation and reduction processes, ionic
competition, hydrolysis, polymerization, and the formation of dissolved salts such as (oxalates and phosphates).
It has inhibitory effects on plants by reducing and delaying growth due to its toxicity, which disrupts various
metabolic activities in cells, such as photosynthesis, respiration, the formation of nucleic acids, the formation of
proteins, as well as the activity and effectiveness of various enzymes and other vital processes that take place
within plants, which ultimately leads to harm to their growth in all its stages and their productive capacity.
Therefore, it poses a threat to life when used as food. The article also highlights the extent to which some plants
growing in environments polluted with heavy metals can store them in their roots while controlling their transfer
from the roots to the stems, leaves and fruits as a type of adaptation to resist the toxicity of these elements. The
greater the amount of heavy metals in the soil, the greater the absorption process by the plant. Plants show
resistance to toxicity to varying degrees by preventing its accumulation in the targeted sites or through the
mechanism of tolerance to these elements when they enter the cytoplasm and when their level increases within
plant tissues. The plant either collects or accumulates them in special locations in the roots, in the vegetative
system, or in the fruits called vesicles, or converts them into other non-toxic forms inside the plant
Keywords
heavy metals
plant growth
Soil pollution.