The assertion describes a state of affairs the place a localized physiological response happens as a consequence of a substance’s introduction into the circulatory system. As an example, an injection website exhibiting redness, swelling, or ache, coupled with the detection of the injected substance within the blood, exemplifies this phenomenon. The substance, initially confined to a particular space, subsequently breaches the barrier and disseminates all through the physique by way of the bloodstream.
Understanding this course of is essential in numerous fields. In pharmacology, it informs the design and administration of medicine to make sure optimum therapeutic results whereas minimizing adversarial reactions. In toxicology, it helps hint the pathways and results of dangerous substances within the physique. Traditionally, tracing the systemic distribution of gear has been instrumental in advancing our information of physiology and illness mechanisms.
The implications of a substance coming into systemic circulation after a localized occasion might be explored in additional element under, masking numerous facets reminiscent of mechanisms of transport, potential results on distant organs, and techniques for managing or mitigating the results.
1. Absorption
Absorption represents the method by which a substance transitions from its website of administration or publicity into the systemic circulation, thereby linking the idea of a localized response to its broader dissemination by means of the bloodstream. Its effectivity and price considerably dictate the magnitude and velocity of systemic results following a localized occasion.
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Mechanisms of Switch
Substances cross organic membranes by way of numerous mechanisms, together with passive diffusion, facilitated diffusion, energetic transport, and endocytosis. The physicochemical properties of the substance (e.g., molecular weight, lipophilicity, cost) affect the dominant mechanism. For instance, small, lipophilic molecules readily diffuse throughout cell membranes, resulting in speedy absorption, whereas bigger, hydrophilic molecules could require provider proteins or vesicular transport. Within the context of a localized response, the effectiveness of absorption mechanisms will decide how rapidly the substance seems within the bloodstream.
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Native Tissue Elements
The traits of the tissue on the website of administration influence absorption. Blood circulation, tissue pH, and the presence of enzymes that may degrade or modify the substance are all crucial. A extremely vascularized tissue will promote sooner absorption in comparison with poorly vascularized tissue. Equally, native pH can affect the ionization state of the substance, affecting its capability to cross cell membranes. Irritation on the website of a localized response can enhance vascular permeability, facilitating absorption, however may set off processes that entice the substance domestically.
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Formulation and Dosage
The formulation of a substance and the dosage administered are crucial determinants of absorption. For instance, an immediate-release formulation will end in sooner absorption in comparison with a sustained-release formulation. Greater doses typically result in better concentrations within the bloodstream, assuming absorption effectivity stays fixed. Understanding the connection between formulation, dosage, and absorption is crucial for predicting systemic results following a localized publicity.
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First-Cross Metabolism
Whereas technically occurring after absorption, first-pass metabolism can considerably cut back the quantity of substance reaching systemic circulation. This primarily happens within the liver and intestine wall for orally administered substances. Nevertheless, for localized reactions reminiscent of intramuscular injections, first-pass metabolism is much less vital however can nonetheless happen to some extent if the substance drains into the lymphatic system and finally enters the portal circulation. Consequently, information of the substance’s susceptibility to first-pass metabolism helps to foretell the proportion that may contribute to systemic results after absorption.
The interaction of those components collectively defines the absorption profile of a substance following a localized occasion. By understanding the mechanisms of switch, native tissue traits, formulation results, and the affect of first-pass metabolism, a extra complete image emerges concerning how and when a domestically confined substance enters the bloodstream and probably triggers systemic results.
2. Distribution
Distribution describes the reversible switch of a substance from one location to a different inside the physique. Following absorption into the bloodstream after a localized occasion, distribution dictates the extent and price at which the substance reaches numerous tissues and organs, influencing the magnitude and period of systemic results.
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Blood Circulation and Tissue Perfusion
Blood circulation to totally different organs and tissues considerably impacts the preliminary distribution of a substance. Extremely perfused organs just like the mind, coronary heart, liver, and kidneys obtain a better proportion of the substance earlier in comparison with poorly perfused tissues reminiscent of adipose tissue or pores and skin. The speed of supply influences the onset and depth of results in these organs. For instance, a quickly distributed toxin could trigger quick neurological results resulting from its swift accumulation within the mind after absorption following a localized publicity.
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Plasma Protein Binding
The diploma to which a substance binds to plasma proteins, reminiscent of albumin, impacts its distribution profile. Protein binding reduces the focus of free (unbound) substance accessible to cross organic membranes and work together with goal tissues. Substances with excessive protein binding have a tendency to stay within the bloodstream longer and exhibit slower distribution to extravascular tissues. This will delay the half-life of the substance and alter its therapeutic or poisonous results. Conversely, low protein binding facilitates speedy distribution into tissues.
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Tissue Binding
Affinity for particular tissues influences the buildup of a substance in these tissues. Some substances exhibit preferential binding to sure tissues resulting from particular receptors, transporters, or physicochemical properties. As an example, lipophilic substances are inclined to accumulate in adipose tissue, performing as a reservoir and prolonging their presence within the physique. Understanding tissue-specific binding is crucial for predicting the potential for localized toxicity or therapeutic results in particular organs following systemic distribution after a localized occasion.
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Blood-Tissue Obstacles
Specialised limitations, such because the blood-brain barrier (BBB), restrict the distribution of sure substances into particular compartments. The BBB restricts the passage of huge or hydrophilic molecules into the mind, defending it from many toxins but additionally hindering the supply of some therapeutic brokers. Substances should possess particular traits, reminiscent of lipophilicity or the power to be actively transported throughout the BBB, to successfully attain the mind. Harm to those limitations, precipitated for instance by irritation, can alter substance distribution patterns and enhance publicity of the protected tissues.
The interaction between blood circulation, protein binding, tissue binding, and blood-tissue limitations collectively determines the distribution sample of a substance after absorption into the bloodstream. This distribution profile is essential for understanding the potential systemic results and toxicity following a localized publicity.
3. Systemic Results
Systemic results symbolize the widespread physiological penalties that come up when a substance, initially launched domestically, enters the bloodstream and is distributed all through the physique. These results are instantly linked to situations the place a localized occasion precipitates the entry of a chemical into the circulatory system, initiating a cascade of responses affecting a number of organ programs.
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Goal Organ Toxicity
Following systemic distribution, chemical substances could exhibit preferential toxicity towards particular organs based mostly on components reminiscent of blood circulation, receptor expression, or metabolic exercise. As an example, a substance absorbed after a localized pores and skin publicity may accumulate within the liver, resulting in hepatotoxicity, or goal the kidneys, leading to nephrotoxicity. The specificity of those results relies on the chemical’s properties and the physiological traits of the goal organ. The severity can fluctuate broadly relying on the focus and period of publicity.
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Cardiovascular Influence
Entry of a chemical into the bloodstream can exert vital results on the cardiovascular system. Vasoconstriction or vasodilation, alterations in coronary heart price or rhythm, and modifications in blood stress are potential outcomes. Anaphylactic shock, triggered by allergens coming into the bloodstream after a localized publicity (e.g., insect sting), is a extreme instance involving widespread vasodilation and hypotension. These cardiovascular results could be life-threatening and require quick intervention.
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Neurological Manifestations
The nervous system is vulnerable to systemic results following chemical entry into the bloodstream. Substances that cross the blood-brain barrier can instantly have an effect on neuronal perform, resulting in a variety of neurological signs. Examples embrace seizures, altered psychological standing, paralysis, or cognitive deficits. The character and severity of those manifestations rely on the precise chemical concerned, its focus within the mind, and particular person susceptibility components.
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Immunological Responses
Chemical substances coming into the bloodstream can set off systemic immune responses. This may increasingly contain the activation of immune cells, the discharge of inflammatory mediators, and the manufacturing of antibodies. Allergic reactions, autoimmune issues, and systemic inflammatory response syndrome (SIRS) are potential penalties. The magnitude and sort of immune response fluctuate relying on the chemical’s properties, the person’s immune standing, and the route of publicity.
The systemic results noticed following a localized occasion that ends in the entry of a chemical into the bloodstream are extremely variable and depending on a posh interaction of things. Understanding these potential penalties is essential for threat evaluation, medical administration, and the event of methods to reduce adversarial outcomes.
4. Toxicity potential
The toxicity potential of a substance is intrinsically linked to situations the place its localized presence ends in entry into the bloodstream. It’s because systemic distribution, enabled by vascular entry, amplifies the potential of adversarial results at websites distant from the preliminary level of contact. A substance with low inherent toxicity may pose minimal threat when confined domestically. Nevertheless, the identical substance, upon coming into systemic circulation, may attain concentrations enough to induce organ injury or disrupt physiological processes. The diploma of toxicity hinges on components such because the substance’s intrinsic properties, the speed and extent of its absorption, and the physique’s capability for detoxing and elimination.
Think about the unintentional injection of a cleansing agent supposed for exterior use. Whereas topical publicity may trigger solely gentle pores and skin irritation, if the identical agent is inadvertently injected, resulting in systemic absorption, the potential for critical penalties will increase. The bloodstream acts as a conduit, delivering the toxicant to susceptible organs just like the liver and kidneys, probably leading to acute organ failure. Conversely, speedy detoxing mechanisms or immediate medical intervention can mitigate the toxicity potential, highlighting the dynamic interaction between publicity and host response. Understanding the substance’s toxicity potential and its capability to enter systemic circulation is essential for threat evaluation and subsequent scientific administration.
In abstract, the chance related to a substance shouldn’t be solely decided by its inherent toxicity, but additionally by its capability to be absorbed into the bloodstream and distributed systemically. Evaluating toxicity potential necessitates contemplating the chance of systemic publicity following a localized occasion, accounting for components that govern absorption, distribution, metabolism, and excretion. Recognition of this connection is crucial for guiding preventive measures, minimizing the chance of adversarial outcomes, and informing acceptable therapeutic methods in circumstances of unintentional or intentional publicity.
5. Dosage relevance
Dosage relevance instantly influences the transition from a localized response to systemic circulation. The amount of a substance launched domestically dictates the focus gradient driving its absorption into the bloodstream. Under a sure threshold dosage, the quantity absorbed could also be inadequate to supply vital systemic results; the substance is perhaps successfully metabolized or sequestered domestically. Nevertheless, exceeding this threshold can overwhelm native detoxing mechanisms and drive a extra substantial fraction of the substance into circulation, resulting in systemic penalties. The connection shouldn’t be linear; components reminiscent of tissue permeability, blood circulation, and binding affinity can modify the dosage-response curve.
An illustrative instance could be discovered within the administration of native anesthetics. A small, localized dose of lidocaine successfully blocks nerve conduction with out systemic toxicity. Nevertheless, unintentional intravascular injection or using extreme doses can lead to vital plasma concentrations. This, in flip, can induce central nervous system results (e.g., seizures) or cardiovascular compromise (e.g., arrhythmias). Equally, a minor pores and skin publicity to a pesticide may trigger a localized rash; nevertheless, a bigger spill resulting in vital dermal absorption and subsequent systemic distribution may end in organophosphate poisoning. This highlights the crucial position of dosage in figuring out the extent and severity of systemic results following a localized occasion.
In conclusion, dosage relevance constitutes a crucial determinant of the systemic sequelae arising from a localized publicity. Understanding the dosage-response relationship for a given substance is crucial for threat evaluation and the event of secure dealing with and administration protocols. Challenges stay in precisely predicting systemic results resulting from inter-individual variability in physiology and metabolic capability. Additional analysis is required to refine dosage tips and personalised approaches to threat administration in circumstances the place localized publicity poses a risk of systemic toxicity.
6. Metabolic pathways
Metabolic pathways play a crucial position in modulating the systemic results following the introduction of a chemical into the bloodstream after a localized response. These pathways govern the biotransformation of the chemical, influencing its focus, persistence, and finally, its toxicity inside the physique. Understanding these pathways is crucial for predicting and mitigating adversarial outcomes.
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Section I Metabolism
Section I metabolic reactions, primarily involving cytochrome P450 enzymes within the liver, introduce or expose useful teams on the chemical construction. This course of can both detoxify the substance by rendering it extra water-soluble and facilitating its excretion or, conversely, activate it right into a extra poisonous metabolite. For instance, the insecticide parathion is comparatively non-toxic till metabolized into paraoxon, a potent cholinesterase inhibitor. Following absorption into the bloodstream after pores and skin contact, the extent of parathion’s conversion to paraoxon dictates the severity of cholinergic signs.
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Section II Metabolism
Section II reactions contain conjugation, the place endogenous molecules reminiscent of glucuronic acid, sulfate, or glutathione are hooked up to the chemical or its Section I metabolites. This typically ends in elevated water solubility and facilitates excretion by means of the kidneys or bile. Nevertheless, some conjugation reactions can paradoxically enhance toxicity. As an example, sure arylamines are N-acetylated within the liver, forming metabolites that may be extra carcinogenic than the mum or dad compound. The stability between activating and detoxifying Section II pathways determines the web impact of metabolism on systemic toxicity after bloodstream entry.
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Genetic Polymorphisms
Genetic variations in metabolic enzymes can considerably influence a person’s capability to course of chemical substances. Polymorphisms in cytochrome P450 enzymes, for instance, can result in both speedy or gradual metabolism of sure medication or toxins. Gradual metabolizers could expertise extended publicity and elevated systemic results following a localized publicity leading to entry to bloodstream, whereas speedy metabolizers may clear the substance rapidly, lowering its toxicity. This inter-individual variability necessitates contemplating genetic components when assessing threat after a localized response that ends in systemic publicity.
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Route of Publicity and First-Cross Metabolism
The route of publicity influences the extent of first-pass metabolism, which happens within the liver and intestine wall earlier than the substance reaches systemic circulation. Substances absorbed by means of the gastrointestinal tract endure in depth first-pass metabolism, probably lowering their bioavailability. Nevertheless, chemical substances absorbed by means of the pores and skin or lungs bypass the liver initially, leading to larger systemic concentrations. Consequently, the identical chemical, coming into the bloodstream after a localized response, could exhibit totally different toxicity profiles relying on the route of publicity and its affect on first-pass metabolism.
In abstract, metabolic pathways are pivotal in figuring out the destiny and toxicity of gear coming into the bloodstream following a localized response. The interaction between Section I and Section II reactions, genetic polymorphisms, and the route of publicity considerably modulates the systemic results. Comprehending these components is crucial for predicting particular person susceptibility and creating tailor-made methods to reduce adversarial well being outcomes.
7. Inflammatory response
The inflammatory response represents a posh cascade of physiological occasions initiated by tissue harm or the presence of international substances. Within the context of a localized response the place a chemical enters the bloodstream, the inflammatory response performs an important position in each containing the insult and mediating systemic results.
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Initiation and Native Vasculature Modifications
Upon chemical entry into the bloodstream following a localized occasion, resident immune cells and endothelial cells on the website launch inflammatory mediators reminiscent of histamine, prostaglandins, and cytokines. These mediators induce vasodilation and elevated vascular permeability. Vasodilation will increase blood circulation to the world, contributing to redness and warmth. Elevated permeability permits fluid and plasma proteins to leak into the encompassing tissue, leading to swelling (edema). These native vascular modifications serve to dilute the chemical and facilitate the recruitment of immune cells.
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Immune Cell Recruitment and Activation
The inflammatory mediators act as chemoattractants, guiding immune cells (e.g., neutrophils, macrophages) from the bloodstream to the location of the response. These cells engulf and degrade the chemical, launch cytotoxic substances, and additional amplify the inflammatory response. The activation of the complement system, triggered by the chemical or by antibodies certain to it, enhances phagocytosis and irritation. Nevertheless, uncontrolled or extreme immune cell activation could cause collateral tissue injury and contribute to the severity of the localized response and subsequent systemic results.
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Systemic Inflammatory Mediator Launch
Because the inflammatory response progresses on the localized website, inflammatory mediators can enter the bloodstream, resulting in systemic results. Cytokines reminiscent of interleukin-1 (IL-1), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-) can induce fever, acute section protein synthesis within the liver, and elevated white blood cell manufacturing within the bone marrow. In extreme circumstances, the systemic launch of inflammatory mediators can set off systemic inflammatory response syndrome (SIRS), characterised by widespread irritation, vasodilation, and potential organ dysfunction.
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Decision and Tissue Restore
The inflammatory response is often a self-limiting course of. Because the chemical is eradicated and the tissue harm is resolved, anti-inflammatory mediators are launched, dampening the inflammatory response. Macrophages take away mobile particles and provoke tissue restore processes. Nevertheless, if the chemical persists or the inflammatory response is dysregulated, power irritation can develop, resulting in tissue fibrosis and long-term issues. Due to this fact, correct decision is essential to reduce long-term penalties.
The inflammatory response, initiated by chemical entry into the bloodstream, represents a double-edged sword. Whereas important for clearing the chemical and initiating tissue restore, extreme or dysregulated irritation can contribute considerably to each native and systemic toxicity. Understanding the nuances of this response is crucial for creating efficient methods to mitigate adversarial results following chemical publicity.
8. Immune activation
The entry of a chemical into the bloodstream following a localized response continuously triggers immune activation, initiating a cascade of occasions supposed to neutralize and eradicate the international substance. This activation can manifest by means of numerous mechanisms, together with the presentation of chemical-derived antigens to T cells, the stimulation of B cells to supply antibodies, and the discharge of pro-inflammatory cytokines by innate immune cells. The magnitude and nature of the immune response rely on the chemical’s properties, the route of entry, and the person’s immune standing. For instance, a hapten, a small molecule that isn’t immunogenic by itself, can bind to a provider protein within the physique and change into a whole antigen, eliciting a powerful immune response upon coming into systemic circulation after a localized pores and skin publicity. Understanding this activation is essential, because it instantly impacts the severity and period of the systemic results ensuing from the publicity.
Immune activation shouldn’t be all the time protecting; it may well contribute to pathological situations. Hypersensitivity reactions, reminiscent of allergic contact dermatitis or drug-induced anaphylaxis, happen when the immune system mounts an exaggerated response to a innocent chemical. In these circumstances, immune activation results in tissue injury and systemic signs. As an example, publicity to poison ivy’s urushiol oil ends in a localized pores and skin response; nevertheless, if the oil is absorbed into the bloodstream, it may well set off a systemic allergic response characterised by widespread dermatitis and probably respiratory misery. Moreover, power publicity to sure chemical substances can result in persistent immune activation, contributing to the event of autoimmune ailments. Recognizing the potential for aberrant immune responses is crucial for acceptable prognosis and administration.
In abstract, immune activation constitutes a significant factor of the systemic response following the entry of a chemical into the bloodstream after a localized response. Whereas the immune system goals to guard the physique from international substances, its activation can even contribute to pathology. Gaining perception into the mechanisms of immune activation and its potential penalties is significant for creating methods to forestall or mitigate adversarial well being results related to chemical exposures. Challenges stay in predicting particular person susceptibility to immune-mediated toxicity and in creating focused therapies to modulate the immune response with out compromising general immune perform.
Regularly Requested Questions Relating to Systemic Absorption Following Localized Chemical Publicity
The next questions handle frequent considerations and misconceptions concerning the entry of chemical substances into the bloodstream after localized reactions, specializing in the scientific and medical facets of this phenomenon.
Query 1: What components decide the speed at which a chemical enters the bloodstream following a localized publicity?
The speed of absorption is influenced by a number of components, together with the chemical’s molecular weight, lipophilicity, focus, and the vascularity of the appliance website. Harm to the pores and skin barrier or the presence of irritation on the website can even enhance absorption charges.
Query 2: How does protein binding have an effect on the distribution of a chemical after it has entered the bloodstream following a localized response?
Binding to plasma proteins, reminiscent of albumin, reduces the free focus of the chemical accessible to cross cell membranes and work together with goal tissues. Excessive protein binding typically slows distribution to tissues and prolongs the chemical’s presence within the bloodstream.
Query 3: What are the potential systemic results of a chemical coming into the bloodstream after a localized publicity?
Systemic results can vary from gentle to extreme and fluctuate relying on the chemical concerned. Potential results embrace goal organ toxicity (e.g., liver, kidneys), cardiovascular results (e.g., arrhythmias, hypotension), neurological manifestations (e.g., seizures, altered psychological standing), and immunological responses (e.g., allergic reactions, anaphylaxis).
Query 4: Can the route of publicity affect the severity of systemic results following bloodstream entry?
Sure. Chemical substances absorbed by means of the pores and skin or lungs could bypass first-pass metabolism within the liver, leading to larger systemic concentrations in comparison with chemical substances ingested orally. This will result in extra pronounced systemic results.
Query 5: How do metabolic pathways have an effect on the toxicity of a chemical after it has entered the bloodstream following a localized response?
Metabolic pathways can both detoxify the chemical by changing it into much less poisonous metabolites or activate it into extra poisonous varieties. Genetic variations in metabolic enzymes can affect a person’s susceptibility to chemical toxicity.
Query 6: What position does the inflammatory response play when a chemical enters the bloodstream after a localized publicity?
The inflammatory response is initiated to comprise and eradicate the chemical. Nevertheless, extreme or dysregulated irritation can contribute to tissue injury and systemic results. Inflammatory mediators launched on the native website can enter the bloodstream and set off systemic inflammatory response syndrome (SIRS).
Understanding the components that govern the entry of chemical substances into the bloodstream, their distribution, metabolism, and results, is crucial for threat evaluation and the event of methods to reduce adversarial well being outcomes following localized chemical exposures.
The dialogue will now transition to methods for prevention and administration of such occasions.
Mitigating Systemic Threat from Localized Chemical Publicity
The next tips define important methods to reduce the potential for localized chemical reactions to progress to systemic absorption and its related dangers. Strict adherence to those rules is essential in each occupational and home settings.
Tip 1: Complete Threat Evaluation: Rigorously consider the potential for localized chemical exposures to result in systemic absorption in particular contexts. This evaluation should take into account the chemical’s properties, potential routes of publicity, and particular person susceptibility components. Documented procedures ought to define preventative measures and emergency response protocols.
Tip 2: Engineering Controls Prioritized: Implement sturdy engineering controls designed to reduce or eradicate direct contact with chemical substances. These controls could embrace enclosed programs, air flow programs with acceptable filtration, and automatic processes to cut back human interplay with hazardous substances. Engineering controls must be favored over private protecting tools (PPE) every time possible.
Tip 3: Correct Private Protecting Tools (PPE): Guarantee acceptable PPE is persistently used when contact with chemical substances can’t be completely eradicated. Collection of PPE should be based mostly on a radical understanding of the chemical’s properties and the precise dangers related to the duty. Common inspection and upkeep of PPE are important for guaranteeing its effectiveness. Coaching on correct donning, doffing, and disposal procedures is necessary.
Tip 4: Stringent Hygiene Practices: Emphasize the significance of rigorous hand hygiene and different private hygiene practices to forestall chemical switch from pores and skin to mucous membranes or ingestion. Work areas should be geared up with readily accessible handwashing services. Consumption of meals and drinks must be strictly prohibited in areas the place chemical substances are dealt with.
Tip 5: Immediate Decontamination Procedures: Set up clear and well-rehearsed procedures for quick decontamination following any potential chemical publicity. Emergency eyewash stations and security showers must be strategically situated and often inspected. Decontamination protocols should be tailor-made to the precise chemical substances concerned.
Tip 6: Medical Surveillance Applications: Implement medical surveillance applications for people prone to chemical publicity. These applications ought to embrace baseline medical evaluations, periodic monitoring of related biomarkers, and immediate investigation of any reported well being considerations. Knowledge from medical surveillance applications can inform threat evaluation and determine potential areas for enchancment in publicity management measures.
Tip 7: Thorough Coaching and Training: Present complete coaching and schooling to all people who deal with or could also be uncovered to chemical substances. This coaching should cowl the hazards related to particular chemical substances, correct dealing with procedures, PPE necessities, emergency response protocols, and the significance of reporting any potential exposures or well being considerations. Coaching must be often up to date to mirror new info or modifications in procedures.
These methods, when diligently applied, supply a sturdy framework for minimizing the chance of systemic absorption following localized chemical publicity. Their effectiveness hinges on a proactive and complete strategy to threat administration, encompassing engineering controls, PPE, hygiene practices, and ongoing coaching.
The following part of this text will deal with emergency response protocols and medical administration following an incident involving systemic chemical publicity.
Conclusion
This text has explored the ramifications of a localized response that ends in a chemical coming into the bloodstream. It has detailed the intricate processes concerned, from preliminary absorption and distribution to the systemic results, toxicity potential, and the modulating affect of metabolic pathways, the inflammatory response, and immune activation. Emphasis has been positioned on the multifaceted components influencing the transition from a confined occasion to a system-wide influence.
A complete understanding of those mechanisms is essential for mitigating the potential hurt arising from such exposures. Continued vigilance in preventative measures, coupled with rigorous adherence to security protocols and immediate medical intervention, stays paramount in safeguarding public well being and minimizing the adversarial penalties when a chemical enters the bloodstream.
