Environmental Chemistry

Course Description

Environmental Chemistry applies basic concepts of organic and inorganic chemistry to environmental topics including water quality, atmospheric pollution, sustainable agriculture, and health risks, combining classroom instruction with field-based learning.

Within the SCNS taxonomy, CHM is the Chemistry prefix, and the 3000-level number places this in the upper division. Daytona State publishes it at 3 credits, prerequisite CHM2211C, offered fall, giving approximately 45 contact hours.

Environmental chemistry is where general chemistry stops being abstract. The reactions are the same ones taught in the introductory sequence — acid-base equilibria, redox, complexation, partitioning — operating in systems that are open, heterogeneous, and running simultaneously. The intellectual step is learning to reason about chemistry outside a beaker, where concentrations are low, matrices are messy, and the answer has consequences.

Learning Outcomes

Required Outcomes

• Describe the major environmental compartments and the movement of chemicals among them.
• Apply equilibrium, kinetics, and thermodynamics to environmental systems.
• Describe aquatic chemistry, including acid-base equilibria, alkalinity, and buffering.
• Describe dissolved oxygen, redox conditions, and their biological consequences.
• Describe the carbonate system and its role in natural waters.
• Describe nutrient chemistry, particularly nitrogen and phosphorus cycling.
• Explain eutrophication chemically and relate it to observed water quality outcomes.
• Describe metal speciation, complexation, and bioavailability.
• Describe sorption, partitioning, and the behaviour of organic contaminants.
• Describe persistence, bioaccumulation, and biomagnification.
• Describe atmospheric chemistry, including photochemical smog and ozone.
• Describe stratospheric ozone depletion and its chemistry.
• Describe greenhouse gases, radiative forcing, and carbon cycling.
• Describe acid deposition and its chemistry and effects.
• Describe particulate matter and air toxics.
• Describe soil chemistry and the chemistry of agricultural inputs.
• Describe pesticide chemistry, fate, and transport.
• Describe toxicology concepts, dose-response, and chemical risk assessment.
• Describe analytical methods used in environmental measurement and their detection limits.
• Apply quality assurance and quality control to environmental sampling and analysis.
• Collect field samples using appropriate technique and preservation.
• Analyze environmental data and report results with appropriate uncertainty.
• Relate chemical findings to environmental regulation and standards.

Optional Outcomes

• Describe green chemistry principles and their application.
• Describe water and wastewater treatment chemistry.
• Describe remediation chemistry for contaminated sites.
• Describe emerging contaminants, including PFAS and pharmaceuticals.
• Describe environmental forensics and source attribution.
• Conduct an independent field and laboratory investigation.

Major Topics

Required Topics

• Environmental compartments and chemical transport
• Equilibrium, kinetics, and thermodynamics in environmental systems
• Aquatic acid-base chemistry and alkalinity
• Dissolved oxygen and redox conditions
• The carbonate system
• Nitrogen and phosphorus cycling
• Eutrophication chemistry
• Metal speciation and bioavailability
• Sorption, partitioning, and organic contaminants
• Persistence, bioaccumulation, biomagnification
• Tropospheric chemistry and photochemical smog
• Stratospheric ozone
• Greenhouse gases and carbon cycling
• Acid deposition
• Particulate matter and air toxics
• Soil chemistry and agricultural inputs
• Pesticide fate and transport
• Toxicology, dose-response, and risk
• Analytical methods and detection limits
• Quality assurance and quality control
• Field sampling technique
• Data analysis and uncertainty
• Chemistry and environmental regulation

Optional Topics

• Green chemistry
• Treatment chemistry
• Remediation chemistry
• Emerging contaminants and PFAS
• Environmental forensics
• Independent investigation

Resources & Tools

• Environmental Chemistry (Stanley Manahan) — the standard comprehensive text; Chemistry of the Environment (Spiro & Stigliani) is the common alternative.
• Aquatic Chemistry (Stumm & Morgan) — the authoritative reference for the water chemistry material; demanding and worth consulting.
• EPA (epa.gov) — free: analytical methods, drinking water standards, the Toxics Release Inventory, and the IRIS toxicity database.
• USGS — free water quality data and the National Water Information System; excellent for comparing your field results against professional monitoring.
• NOAA and the Florida Fish and Wildlife Research Institute — free harmful algal bloom monitoring and data.
• Florida DEP (floridadep.gov) — free: Florida water quality standards, impaired waters listings, and the springs monitoring programme.
• NIST Chemistry WebBook — free thermodynamic and spectroscopic reference data.
• PubChem — free chemical property data, useful for partitioning and fate estimation.
• Field and laboratory equipment as supplied — meters, sampling apparatus, and instrumental analysis access.
• A bound field notebook — see the QA/QC flag below.

Career Pathways

• Environmental chemist — laboratories, consultancies, and agencies.
• Analytical chemist — environmental testing laboratories, which are numerous in Florida.
• Environmental scientist and consultant — site assessment, monitoring, and compliance.
• Water quality specialist — utilities, water management districts, and DEP.
• Regulatory and compliance roles — industry and government.
• Environmental engineering — with an engineering degree; the chemistry is the foundation.
• Public health and toxicology — with further study.
• Agricultural and soil science — a substantial Florida sector.
• Graduate study — environmental chemistry, environmental engineering, oceanography, or geochemistry.
• SOC codes 19-2031 Chemists, 19-2041 Environmental Scientists and Specialists, and 19-4042 Environmental Science and Protection Technicians.

Special Information

⚠ Speciation determines everything — total concentration is frequently the wrong number

The conceptual step that separates environmental chemistry from analytical chemistry, and it is the course's most transferable idea.

What a chemical does in the environment depends on what form it is in, not on how much of it is present in total. The same element can be inert, mobile, bioavailable, or acutely toxic depending on oxidation state, complexation, and the surrounding chemistry.

• Metals are the clearest case. Chromium(III) is a required trace nutrient; chromium(VI) is a carcinogen. Free metal ion activity, not total metal, generally governs toxicity — which is why total-metal analysis can over- or under-state risk substantially.
• pH drives speciation. It controls metal solubility, ammonia versus ammonium, the carbonate system, and the ionization of organic acids and bases — which in turn controls their mobility and uptake.
• Redox conditions matter as much as pH. Iron and manganese mobilize under reducing conditions; nitrate becomes nitrogen gas; sulfate becomes sulfide. A change in oxygen status changes the chemistry of an entire system.
• Complexation and sorption reduce availability. Natural organic matter binds metals; clays and organic carbon sorb hydrophobic organics — which means a contaminant present in sediment may be effectively unavailable, or may be released when conditions change.
• Partitioning predicts fate. Octanol-water and organic carbon partition coefficients, Henry's law constants, and vapour pressure together tell you whether a compound ends up in water, sediment, air, or biota.
• Bioaccumulation follows from partitioning — hydrophobic, persistent compounds concentrate up food chains, which is why top predators carry the highest burdens.

The practical consequence: ask what form, in what matrix, under what conditions before interpreting any environmental concentration.

⚠ Florida's chemistry is distinctive — karst, nutrients, and a shallow water table

The regional application, and the field component makes it concrete.

• Karst geology dominates. Limestone bedrock means the aquifer is chemically active — carbonate dissolution buffers water strongly, produces high alkalinity and hardness, and creates rapid conduit flow. Contaminants reach groundwater faster here than in most places and receive less filtration.
• Springs are chemical windows into the aquifer. Their chemistry — nitrate especially — is a direct indicator of what is entering the groundwater, and Florida spring nitrate increases are documented and politically salient.
• Nutrient chemistry is the state's central water quality problem. Nitrogen from fertilizer, septic systems, and agriculture, and phosphorus from historical and current sources, drive eutrophication in springs, lakes, rivers, and estuaries.
• Harmful algal blooms are the visible consequence — cyanobacteria inland producing microcystins and other toxins, and Karenia brevis red tide on the Gulf coast producing brevetoxins with respiratory effects. Both are chemistry problems with public health consequences.
• Phosphate mining and phosphogypsum are a distinctive Florida issue, involving radionuclides, acidity, and very large volumes of process water.
• Saltwater intrusion changes ionic strength and speciation in coastal aquifers, with consequences for treatment and for infrastructure.
• Warm temperatures accelerate reaction rates and biological activity, and high organic loading in wetlands drives strongly reducing conditions — Florida's chemistry does not behave like a temperate textbook.

Local data is public and free — DEP, the water management districts, and USGS all publish it, which makes comparing your field results against professional monitoring straightforward and genuinely instructive.

⚠ QA/QC is the difference between a measurement and a number

The professional discipline that environmental chemistry requires and that classroom chemistry does not teach.

• Environmental concentrations are low and matrices are complex, which means contamination, interference, and loss during handling are constant threats. A result without quality control behind it is not evidence.
• Blanks tell you about your own procedure. A field blank that reads high means the contamination is yours, not the environment's — and this is the most common source of false positives in student work.
• Duplicates measure precision, and spikes and recovery measure accuracy in the actual matrix rather than in clean water.
• Calibrate, and know your detection limit. A result below detection is not zero, and reporting it as zero is wrong; the correct statement is that it was below a stated limit.
• Preservation and holding times are method requirements. Samples for metals, nutrients, and organics each require specific containers, preservatives, and maximum holding times — exceeding them invalidates the result regardless of how good the analysis was.
• Chain of custody exists because environmental data becomes legal evidence in permits, enforcement, and litigation. A sample whose handling cannot be documented is not usable.
• Report uncertainty honestly. A concentration without a range or a stated method precision overstates what you know, and significant figures are a claim about precision.
• Report what you measured, including inconvenient results. Adjusting data toward the expected answer is the failure mode that ends environmental careers, and environmental data has consequences.

⚠ Chemistry meets regulation and risk communication — both are part of the job

• Standards are chemistry plus policy. A drinking water maximum contaminant level reflects toxicity, analytical capability, treatment feasibility, and cost — not toxicity alone. Understanding that prevents both naive alarm and naive reassurance.
• Detection improved faster than toxicology. Modern instruments detect compounds at concentrations far below any established effect level, which means "detected" and "harmful" have drifted apart — and public communication frequently conflates them.
• PFAS is the current case study. Extremely persistent, mobile, detected widely, and with health advisory and regulatory levels that have moved sharply downward as toxicology developed. This is an area changing quickly and worth following in primary sources.
• Dose-response is the frame. The dose makes the poison, thresholds and non-threshold models differ, and extrapolating from high-dose animal studies to low-dose human exposure introduces large uncertainty. See this repository's EVR2630 guide for the risk assessment framework.
• Communicate honestly in both directions. Overstating risk destroys credibility; dismissing a community's concern because a concentration is below a standard misses that standards are provisional and that people are entitled to ask.
• Environmental justice is a chemistry issue too — exposure is unevenly distributed, and the communities nearest to sources are frequently those with least capacity to respond.

Rule 11 applies with force — drinking water standards, PFAS regulation, and toxicity values are actively changing. Verify against current EPA and DEP sources rather than a textbook.

⚠ Only about three Florida institutions carry this number — hedge accordingly

This course appears at roughly three institutions statewide. Content, credit value, and emphasis vary more than they would for a widely taught course. Read your own institution's catalog description and syllabus rather than assuming this guide describes your section exactly, and have any transfer evaluated in writing.

How Florida course levels affect transfer

The first digit of an SCNS number denotes the year of offering, not transferability. Courses at the 1000 and 2000 levels transfer transparently between Florida public institutions, and 3000 to 4000 is unproblematic since both are upper division. The boundary that actually matters is 2000 to 3000, where lower-division credit generally cannot satisfy an upper-division requirement.

CHM3085 is 3 credits and approximately 45 contact hours, offered fall, and the catalog specifies field-based learning alongside classroom instruction. Expect sampling, analysis, and a written report; the field component is where the QA/QC discipline becomes real.

CHM3085 is upper division with a genuine organic chemistry prerequisite — a lower-division environmental science course will not substitute. Students arriving from an A.A. hold junior standing under Florida's articulation agreement, but should confirm that CHM2211C or its equivalent is complete, since the prerequisite is used rather than nominal.